All C# errors and warnings

Parsed from the Roslyn source code using Roslyn.

Code	Severity	Message
CS0006	Error	Metadata file '{0}' could not be found
CS0009	Fatal	Metadata file '{0}' could not be opened -- {1}
CS0012	Error	The type '{0}' is defined in an assembly that is not referenced. You must add a reference to assembly '{1}'.
CS0016	Error	Could not write to output file '{0}' -- '{1}'
CS0017	Error	Program has more than one entry point defined. Compile with /main to specify the type that contains the entry point.
CS0019	Error	Operator '{0}' cannot be applied to operands of type '{1}' and '{2}'
CS0020	Error	Division by constant zero
CS0021	Error	Cannot apply indexing with [] to an expression of type '{0}'
CS0022	Error	Wrong number of indices inside []; expected {0}
CS0023	Error	Operator '{0}' cannot be applied to operand of type '{1}'
CS0026	Error	Keyword 'this' is not valid in a static property, static method, or static field initializer
CS0027	Error	Keyword 'this' is not available in the current context
CS0028	Warning	'{0}' has the wrong signature to be an entry point
CS0029	Error	Cannot implicitly convert type '{0}' to '{1}'
CS0030	Error	Cannot convert type '{0}' to '{1}'
CS0031	Error	Constant value '{0}' cannot be converted to a '{1}'
CS0034	Error	Operator '{0}' is ambiguous on operands of type '{1}' and '{2}'
CS0035	Error	Operator '{0}' is ambiguous on an operand of type '{1}'
CS0036	Error	An out parameter cannot have the In attribute
CS0037	Error	Cannot convert null to '{0}' because it is a non-nullable value type
CS0039	Error	Cannot convert type '{0}' to '{1}' via a reference conversion, boxing conversion, unboxing conversion, wrapping conversion, or null type conversion
CS0041	Fatal	Unexpected error writing debug information -- '{0}'
CS0050	Error	Inconsistent accessibility: return type '{1}' is less accessible than method '{0}'
CS0051	Error	Inconsistent accessibility: parameter type '{1}' is less accessible than method '{0}'
CS0052	Error	Inconsistent accessibility: field type '{1}' is less accessible than field '{0}'
CS0053	Error	Inconsistent accessibility: property type '{1}' is less accessible than property '{0}'
CS0054	Error	Inconsistent accessibility: indexer return type '{1}' is less accessible than indexer '{0}'
CS0055	Error	Inconsistent accessibility: parameter type '{1}' is less accessible than indexer '{0}'
CS0056	Error	Inconsistent accessibility: return type '{1}' is less accessible than operator '{0}'
CS0057	Error	Inconsistent accessibility: parameter type '{1}' is less accessible than operator '{0}'
CS0058	Error	Inconsistent accessibility: return type '{1}' is less accessible than delegate '{0}'
CS0059	Error	Inconsistent accessibility: parameter type '{1}' is less accessible than delegate '{0}'
CS0060	Error	Inconsistent accessibility: base class '{1}' is less accessible than class '{0}'
CS0061	Error	Inconsistent accessibility: base interface '{1}' is less accessible than interface '{0}'
CS0065	Error	'{0}': event property must have both add and remove accessors
CS0066	Error	'{0}': event must be of a delegate type
CS0067	Warning	The event '{0}' is never used
CS0068	Error	'{0}': instance event in interface cannot have initializer
CS0070	Error	The event '{0}' can only appear on the left hand side of += or -= (except when used from within the type '{1}')
CS0071	Error	An explicit interface implementation of an event must use event accessor syntax
CS0072	Error	'{0}': cannot override; '{1}' is not an event
CS0073	Error	An add or remove accessor must have a body
CS0074	Error	'{0}': abstract event cannot have initializer
CS0075	Error	To cast a negative value, you must enclose the value in parentheses.
CS0076	Error	The enumerator name '{0}' is reserved and cannot be used
CS0077	Error	The as operator must be used with a reference type or nullable type ('{0}' is a non-nullable value type)
CS0078	Warning	The 'l' suffix is easily confused with the digit '1' -- use 'L' for clarity
CS0079	Error	The event '{0}' can only appear on the left hand side of += or -=
CS0080	Error	Constraints are not allowed on non-generic declarations
CS0081	Error	Type parameter declaration must be an identifier not a type
CS0082	Error	Type '{1}' already reserves a member called '{0}' with the same parameter types
CS0100	Error	The parameter name '{0}' is a duplicate
CS0101	Error	The namespace '{1}' already contains a definition for '{0}'
CS0102	Error	The type '{0}' already contains a definition for '{1}'
CS0103	Error	The name '{0}' does not exist in the current context
CS0104	Error	'{0}' is an ambiguous reference between '{1}' and '{2}'
CS0105	Warning	The using directive for '{0}' appeared previously in this namespace
CS0106	Error	The modifier '{0}' is not valid for this item
CS0107	Error	More than one protection modifier
CS0108	Warning	'{0}' hides inherited member '{1}'. Use the new keyword if hiding was intended.
CS0109	Warning	The member '{0}' does not hide an accessible member. The new keyword is not required.
CS0110	Error	The evaluation of the constant value for '{0}' involves a circular definition
CS0111	Error	Type '{1}' already defines a member called '{0}' with the same parameter types
CS0112	Error	A static member '{0}' cannot be marked as override, virtual, or abstract
CS0113	Error	A member '{0}' marked as override cannot be marked as new or virtual
CS0114	Warning	'{0}' hides inherited member '{1}'. To make the current member override that implementation, add the override keyword. Otherwise add the new keyword.
CS0115	Error	'{0}': no suitable method found to override
CS0116	Error	A namespace cannot directly contain members such as fields or methods
CS0117	Error	'{0}' does not contain a definition for '{1}'
CS0118	Error	'{0}' is a {1} but is used like a {2}
CS0119	Error	'{0}' is a {1}, which is not valid in the given context
CS0120	Error	An object reference is required for the non-static field, method, or property '{0}'
CS0121	Error	The call is ambiguous between the following methods or properties: '{0}' and '{1}'
CS0122	Error	'{0}' is inaccessible due to its protection level
CS0123	Error	No overload for '{0}' matches delegate '{1}'
CS0126	Error	An object of a type convertible to '{0}' is required
CS0127	Error	Since '{0}' returns void, a return keyword must not be followed by an object expression
CS0128	Error	A local variable or function named '{0}' is already defined in this scope
CS0131	Error	The left-hand side of an assignment must be a variable, property or indexer
CS0132	Error	'{0}': a static constructor must be parameterless
CS0133	Error	The expression being assigned to '{0}' must be constant
CS0134	Error	'{0}' is of type '{1}'. A const field of a reference type other than string can only be initialized with null.
CS0136	Error	A local or parameter named '{0}' cannot be declared in this scope because that name is used in an enclosing local scope to define a local or parameter
CS0138	Error	A 'using namespace' directive can only be applied to namespaces; '{0}' is a type not a namespace. Consider a 'using static' directive instead
CS0139	Error	No enclosing loop out of which to break or continue
CS0140	Error	The label '{0}' is a duplicate
CS0143	Error	The type '{0}' has no constructors defined
CS0144	Error	Cannot create an instance of the abstract class or interface '{0}'
CS0145	Error	A const field requires a value to be provided
CS0146	Error	Circular base class dependency involving '{0}' and '{1}'
CS0148	Error	The delegate '{0}' does not have a valid constructor
CS0149	Error	Method name expected
CS0150	Error	A constant value is expected
CS0151	Error	A switch expression or case label must be a bool, char, string, integral, enum, or corresponding nullable type in C# 6 and earlier.
CS0152	Error	The switch statement contains multiple cases with the label value '{0}'
CS0153	Error	A goto case is only valid inside a switch statement
CS0154	Error	The property or indexer '{0}' cannot be used in this context because it lacks the get accessor
CS0155	Error	The type caught or thrown must be derived from System.Exception
CS0156	Error	A throw statement with no arguments is not allowed outside of a catch clause
CS0157	Error	Control cannot leave the body of a finally clause
CS0158	Error	The label '{0}' shadows another label by the same name in a contained scope
CS0159	Error	No such label '{0}' within the scope of the goto statement
CS0160	Error	A previous catch clause already catches all exceptions of this or of a super type ('{0}')
CS0161	Error	'{0}': not all code paths return a value
CS0162	Warning	Unreachable code detected
CS0163	Error	Control cannot fall through from one case label ('{0}') to another
CS0164	Warning	This label has not been referenced
CS0165	Error	Use of unassigned local variable '{0}'
CS0168	Warning	The variable '{0}' is declared but never used
CS0169	Warning	The field '{0}' is never used
CS0170	Error	Use of possibly unassigned field '{0}'
CS0171	Error	Field '{0}' must be fully assigned before control is returned to the caller
CS0172	Error	Type of conditional expression cannot be determined because '{0}' and '{1}' implicitly convert to one another
CS0173	Error	Type of conditional expression cannot be determined because there is no implicit conversion between '{0}' and '{1}'
CS0174	Error	A base class is required for a 'base' reference
CS0175	Error	Use of keyword 'base' is not valid in this context
CS0176	Error	Member '{0}' cannot be accessed with an instance reference; qualify it with a type name instead
CS0177	Error	The out parameter '{0}' must be assigned to before control leaves the current method
CS0178	Error	Invalid rank specifier: expected ',' or ']'
CS0179	Error	'{0}' cannot be extern and declare a body
CS0180	Error	'{0}' cannot be both extern and abstract
CS0181	Error	Attribute constructor parameter '{0}' has type '{1}', which is not a valid attribute parameter type
CS0182	Error	An attribute argument must be a constant expression, typeof expression or array creation expression of an attribute parameter type
CS0183	Warning	The given expression is always of the provided ('{0}') type
CS0184	Warning	The given expression is never of the provided ('{0}') type
CS0185	Error	'{0}' is not a reference type as required by the lock statement
CS0186	Error	Use of null is not valid in this context
CS0188	Error	The 'this' object cannot be used before all of its fields are assigned to
CS0190	Error	The __arglist construct is valid only within a variable argument method
CS0191	Error	A readonly field cannot be assigned to (except in a constructor or a variable initializer)
CS0192	Error	A readonly field cannot be used as a ref or out value (except in a constructor)
CS0193	Error	The * or -> operator must be applied to a pointer
CS0196	Error	A pointer must be indexed by only one value
CS0197	Warning	Using '{0}' as a ref or out value or taking its address may cause a runtime exception because it is a field of a marshal-by-reference class
CS0198	Error	A static readonly field cannot be assigned to (except in a static constructor or a variable initializer)
CS0199	Error	A static readonly field cannot be used as a ref or out value (except in a static constructor)
CS0200	Error	Property or indexer '{0}' cannot be assigned to -- it is read only
CS0201	Error	Only assignment, call, increment, decrement, await, and new object expressions can be used as a statement
CS0202	Error	foreach requires that the return type '{0}' of '{1}' must have a suitable public 'MoveNext' method and public 'Current' property
CS0204	Error	Only 65534 locals, including those generated by the compiler, are allowed
CS0205	Error	Cannot call an abstract base member: '{0}'
CS0206	Error	A property or indexer may not be passed as an out or ref parameter
CS0208	Error	Cannot take the address of, get the size of, or declare a pointer to a managed type ('{0}')
CS0209	Error	The type of a local declared in a fixed statement must be a pointer type
CS0210	Error	You must provide an initializer in a fixed or using statement declaration
CS0211	Error	Cannot take the address of the given expression
CS0212	Error	You can only take the address of an unfixed expression inside of a fixed statement initializer
CS0213	Error	You cannot use the fixed statement to take the address of an already fixed expression
CS0214	Error	Pointers and fixed size buffers may only be used in an unsafe context
CS0215	Error	The return type of operator True or False must be bool
CS0216	Error	The operator '{0}' requires a matching operator '{1}' to also be defined
CS0217	Error	In order to be applicable as a short circuit operator a user-defined logical operator ('{0}') must have the same return type and parameter types
CS0218	Error	In order for '{0}' to be applicable as a short circuit operator, its declaring type '{1}' must define operator true and operator false
CS0219	Warning	The variable '{0}' is assigned but its value is never used
CS0220	Error	The operation overflows at compile time in checked mode
CS0221	Error	Constant value '{0}' cannot be converted to a '{1}' (use 'unchecked' syntax to override)
CS0224	Error	A method with vararg cannot be generic, be in a generic type, or have a params parameter
CS0225	Error	The params parameter must be a single dimensional array
CS0226	Error	An __arglist expression may only appear inside of a call or new expression
CS0227	Error	Unsafe code may only appear if compiling with /unsafe
CS0229	Error	Ambiguity between '{0}' and '{1}'
CS0230	Error	Type and identifier are both required in a foreach statement
CS0231	Error	A params parameter must be the last parameter in a formal parameter list
CS0233	Error	'{0}' does not have a predefined size, therefore sizeof can only be used in an unsafe context
CS0234	Error	The type or namespace name '{0}' does not exist in the namespace '{1}' (are you missing an assembly reference?)
CS0236	Error	A field initializer cannot reference the non-static field, method, or property '{0}'
CS0238	Error	'{0}' cannot be sealed because it is not an override
CS0239	Error	'{0}': cannot override inherited member '{1}' because it is sealed
CS0242	Error	The operation in question is undefined on void pointers
CS0243	Error	The Conditional attribute is not valid on '{0}' because it is an override method
CS0244	Error	Neither 'is' nor 'as' is valid on pointer types
CS0245	Error	Destructors and object.Finalize cannot be called directly. Consider calling IDisposable.Dispose if available.
CS0246	Error	The type or namespace name '{0}' could not be found (are you missing a using directive or an assembly reference?)
CS0247	Error	Cannot use a negative size with stackalloc
CS0248	Error	Cannot create an array with a negative size
CS0249	Error	Do not override object.Finalize. Instead, provide a destructor.
CS0250	Error	Do not directly call your base class Finalize method. It is called automatically from your destructor.
CS0251	Warning	Indexing an array with a negative index (array indices always start at zero)
CS0252	Warning	Possible unintended reference comparison; to get a value comparison, cast the left hand side to type '{0}'
CS0253	Warning	Possible unintended reference comparison; to get a value comparison, cast the right hand side to type '{0}'
CS0254	Error	The right hand side of a fixed statement assignment may not be a cast expression
CS0255	Error	stackalloc may not be used in a catch or finally block
CS0257	Error	An __arglist parameter must be the last parameter in a formal parameter list
CS0260	Error	Missing partial modifier on declaration of type '{0}'; another partial declaration of this type exists
CS0261	Error	Partial declarations of '{0}' must be all classes, all structs, or all interfaces
CS0262	Error	Partial declarations of '{0}' have conflicting accessibility modifiers
CS0263	Error	Partial declarations of '{0}' must not specify different base classes
CS0264	Error	Partial declarations of '{0}' must have the same type parameter names in the same order
CS0265	Error	Partial declarations of '{0}' have inconsistent constraints for type parameter '{1}'
CS0266	Error	Cannot implicitly convert type '{0}' to '{1}'. An explicit conversion exists (are you missing a cast?)
CS0267	Error	The 'partial' modifier can only appear immediately before 'class', 'struct', 'interface', or 'void'
CS0268	Error	Imported type '{0}' is invalid. It contains a circular base class dependency.
CS0269	Error	Use of unassigned out parameter '{0}'
CS0270	Error	Array size cannot be specified in a variable declaration (try initializing with a 'new' expression)
CS0271	Error	The property or indexer '{0}' cannot be used in this context because the get accessor is inaccessible
CS0272	Error	The property or indexer '{0}' cannot be used in this context because the set accessor is inaccessible
CS0273	Error	The accessibility modifier of the '{0}' accessor must be more restrictive than the property or indexer '{1}'
CS0274	Error	Cannot specify accessibility modifiers for both accessors of the property or indexer '{0}'
CS0276	Error	'{0}': accessibility modifiers on accessors may only be used if the property or indexer has both a get and a set accessor
CS0277	Error	'{0}' does not implement interface member '{1}'. '{2}' is not public.
CS0278	Warning	'{0}' does not implement the '{1}' pattern. '{2}' is ambiguous with '{3}'.
CS0279	Warning	'{0}' does not implement the '{1}' pattern. '{2}' is either static or not public.
CS0280	Warning	'{0}' does not implement the '{1}' pattern. '{2}' has the wrong signature.
CS0281	Error	Friend access was granted by '{0}', but the public key of the output assembly ('{1}') does not match that specified by the InternalsVisibleTo attribute in the granting assembly.
CS0282	Warning	There is no defined ordering between fields in multiple declarations of partial struct '{0}'. To specify an ordering, all instance fields must be in the same declaration.
CS0283	Error	The type '{0}' cannot be declared const
CS0304	Error	Cannot create an instance of the variable type '{0}' because it does not have the new() constraint
CS0305	Error	Using the generic {1} '{0}' requires {2} type arguments
CS0306	Error	The type '{0}' may not be used as a type argument
CS0307	Error	The {1} '{0}' cannot be used with type arguments
CS0308	Error	The non-generic {1} '{0}' cannot be used with type arguments
CS0310	Error	'{2}' must be a non-abstract type with a public parameterless constructor in order to use it as parameter '{1}' in the generic type or method '{0}'
CS0311	Error	The type '{3}' cannot be used as type parameter '{2}' in the generic type or method '{0}'. There is no implicit reference conversion from '{3}' to '{1}'.
CS0312	Error	The type '{3}' cannot be used as type parameter '{2}' in the generic type or method '{0}'. The nullable type '{3}' does not satisfy the constraint of '{1}'.
CS0313	Error	The type '{3}' cannot be used as type parameter '{2}' in the generic type or method '{0}'. The nullable type '{3}' does not satisfy the constraint of '{1}'. Nullable types can not satisfy any interface constraints.
CS0314	Error	The type '{3}' cannot be used as type parameter '{2}' in the generic type or method '{0}'. There is no boxing conversion or type parameter conversion from '{3}' to '{1}'.
CS0315	Error	The type '{3}' cannot be used as type parameter '{2}' in the generic type or method '{0}'. There is no boxing conversion from '{3}' to '{1}'.
CS0316	Error	The parameter name '{0}' conflicts with an automatically-generated parameter name
CS0400	Error	The type or namespace name '{0}' could not be found in the global namespace (are you missing an assembly reference?)
CS0401	Error	The new() constraint must be the last constraint specified
CS0402	Warning	'{0}': an entry point cannot be generic or in a generic type
CS0403	Error	Cannot convert null to type parameter '{0}' because it could be a non-nullable value type. Consider using 'default({0})' instead.
CS0404	Error	Cannot apply attribute class '{0}' because it is generic
CS0405	Error	Duplicate constraint '{0}' for type parameter '{1}'
CS0406	Error	The class type constraint '{0}' must come before any other constraints
CS0407	Error	'{1} {0}' has the wrong return type
CS0409	Error	A constraint clause has already been specified for type parameter '{0}'. All of the constraints for a type parameter must be specified in a single where clause.
CS0411	Error	The type arguments for method '{0}' cannot be inferred from the usage. Try specifying the type arguments explicitly.
CS0412	Error	'{0}': a parameter, local variable, or local function cannot have the same name as a method type parameter
CS0413	Error	The type parameter '{0}' cannot be used with the 'as' operator because it does not have a class type constraint nor a 'class' constraint
CS0414	Warning	The field '{0}' is assigned but its value is never used
CS0415	Error	The '{0}' attribute is valid only on an indexer that is not an explicit interface member declaration
CS0416	Error	'{0}': an attribute argument cannot use type parameters
CS0417	Error	'{0}': cannot provide arguments when creating an instance of a variable type
CS0418	Error	'{0}': an abstract class cannot be sealed or static
CS0419	Warning	Ambiguous reference in cref attribute: '{0}'. Assuming '{1}', but could have also matched other overloads including '{2}'.
CS0420	Warning	'{0}': a reference to a volatile field will not be treated as volatile
CS0423	Error	Since '{1}' has the ComImport attribute, '{0}' must be extern or abstract
CS0424	Error	'{0}': a class with the ComImport attribute cannot specify a base class
CS0425	Error	The constraints for type parameter '{0}' of method '{1}' must match the constraints for type parameter '{2}' of interface method '{3}'. Consider using an explicit interface implementation instead.
CS0426	Error	The type name '{0}' does not exist in the type '{1}'
CS0428	Error	Cannot convert method group '{0}' to non-delegate type '{1}'. Did you intend to invoke the method?
CS0430	Error	The extern alias '{0}' was not specified in a /reference option
CS0431	Error	Cannot use alias '{0}' with '::' since the alias references a type. Use '.' instead.
CS0432	Error	Alias '{0}' not found
CS0433	Error	The type '{1}' exists in both '{0}' and '{2}'
CS0434	Error	The namespace '{1}' in '{0}' conflicts with the type '{3}' in '{2}'
CS0435	Warning	The namespace '{1}' in '{0}' conflicts with the imported type '{3}' in '{2}'. Using the namespace defined in '{0}'.
CS0436	Warning	The type '{1}' in '{0}' conflicts with the imported type '{3}' in '{2}'. Using the type defined in '{0}'.
CS0437	Warning	The type '{1}' in '{0}' conflicts with the imported namespace '{3}' in '{2}'. Using the type defined in '{0}'.
CS0438	Error	The type '{1}' in '{0}' conflicts with the namespace '{3}' in '{2}'
CS0439	Error	An extern alias declaration must precede all other elements defined in the namespace
CS0440	Warning	Defining an alias named 'global' is ill-advised since 'global::' always references the global namespace and not an alias
CS0441	Error	'{0}': a class cannot be both static and sealed
CS0442	Error	'{0}': abstract properties cannot have private accessors
CS0443	Error	Syntax error; value expected
CS0445	Error	Cannot modify the result of an unboxing conversion
CS0446	Error	Foreach cannot operate on a '{0}'. Did you intend to invoke the '{0}'?
CS0448	Error	The return type for ++ or -- operator must match the parameter type or be derived from the parameter type
CS0449	Error	The 'class' or 'struct' constraint must come before any other constraints
CS0450	Error	'{0}': cannot specify both a constraint class and the 'class' or 'struct' constraint
CS0451	Error	The 'new()' constraint cannot be used with the 'struct' constraint
CS0452	Error	The type '{2}' must be a reference type in order to use it as parameter '{1}' in the generic type or method '{0}'
CS0453	Error	The type '{2}' must be a non-nullable value type in order to use it as parameter '{1}' in the generic type or method '{0}'
CS0454	Error	Circular constraint dependency involving '{0}' and '{1}'
CS0455	Error	Type parameter '{0}' inherits conflicting constraints '{1}' and '{2}'
CS0456	Error	Type parameter '{1}' has the 'struct' constraint so '{1}' cannot be used as a constraint for '{0}'
CS0457	Error	Ambiguous user defined conversions '{0}' and '{1}' when converting from '{2}' to '{3}'
CS0458	Warning	The result of the expression is always 'null' of type '{0}'
CS0460	Error	Constraints for override and explicit interface implementation methods are inherited from the base method, so they cannot be specified directly, except for either a 'class', or a 'struct' constraint.
CS0462	Error	The inherited members '{0}' and '{1}' have the same signature in type '{2}', so they cannot be overridden
CS0463	Error	Evaluation of the decimal constant expression failed
CS0464	Warning	Comparing with null of type '{0}' always produces 'false'
CS0465	Warning	Introducing a 'Finalize' method can interfere with destructor invocation. Did you intend to declare a destructor?
CS0466	Error	'{0}' should not have a params parameter since '{1}' does not
CS0469	Warning	The 'goto case' value is not implicitly convertible to type '{0}'
CS0470	Error	Method '{0}' cannot implement interface accessor '{1}' for type '{2}'. Use an explicit interface implementation.
CS0472	Warning	The result of the expression is always '{0}' since a value of type '{1}' is never equal to 'null' of type '{2}'
CS0473	Warning	Explicit interface implementation '{0}' matches more than one interface member. Which interface member is actually chosen is implementation-dependent. Consider using a non-explicit implementation instead.
CS0500	Error	'{0}' cannot declare a body because it is marked abstract
CS0501	Error	'{0}' must declare a body because it is not marked abstract, extern, or partial
CS0502	Error	'{0}' cannot be both abstract and sealed
CS0503	Error	The abstract {0} '{1}' cannot be marked virtual
CS0504	Error	The constant '{0}' cannot be marked static
CS0505	Error	'{0}': cannot override because '{1}' is not a function
CS0506	Error	'{0}': cannot override inherited member '{1}' because it is not marked virtual, abstract, or override
CS0507	Error	'{0}': cannot change access modifiers when overriding '{1}' inherited member '{2}'
CS0508	Error	'{0}': return type must be '{2}' to match overridden member '{1}'
CS0509	Error	'{0}': cannot derive from sealed type '{1}'
CS0513	Error	'{0}' is abstract but it is contained in non-abstract class '{1}'
CS0514	Error	'{0}': static constructor cannot have an explicit 'this' or 'base' constructor call
CS0515	Error	'{0}': access modifiers are not allowed on static constructors
CS0516	Error	Constructor '{0}' cannot call itself
CS0517	Error	'{0}' has no base class and cannot call a base constructor
CS0518	Error	Predefined type '{0}' is not defined or imported
CS0522	Error	'{0}': structs cannot call base class constructors
CS0523	Error	Struct member '{0}' of type '{1}' causes a cycle in the struct layout
CS0525	Error	Interfaces cannot contain instance fields
CS0526	Error	Interfaces cannot contain instance constructors
CS0527	Error	Type '{0}' in interface list is not an interface
CS0528	Error	'{0}' is already listed in interface list
CS0529	Error	Inherited interface '{1}' causes a cycle in the interface hierarchy of '{0}'
CS0533	Error	'{0}' hides inherited abstract member '{1}'
CS0534	Error	'{0}' does not implement inherited abstract member '{1}'
CS0535	Error	'{0}' does not implement interface member '{1}'
CS0537	Error	The class System.Object cannot have a base class or implement an interface
CS0538	Error	'{0}' in explicit interface declaration is not an interface
CS0539	Error	'{0}' in explicit interface declaration is not found among members of the interface that can be implemented
CS0540	Error	'{0}': containing type does not implement interface '{1}'
CS0541	Error	'{0}': explicit interface declaration can only be declared in a class, struct or interface
CS0542	Error	'{0}': member names cannot be the same as their enclosing type
CS0543	Error	'{0}': the enumerator value is too large to fit in its type
CS0544	Error	'{0}': cannot override because '{1}' is not a property
CS0545	Error	'{0}': cannot override because '{1}' does not have an overridable get accessor
CS0546	Error	'{0}': cannot override because '{1}' does not have an overridable set accessor
CS0547	Error	'{0}': property or indexer cannot have void type
CS0548	Error	'{0}': property or indexer must have at least one accessor
CS0549	Error	'{0}' is a new virtual member in sealed class '{1}'
CS0550	Error	'{0}' adds an accessor not found in interface member '{1}'
CS0551	Error	Explicit interface implementation '{0}' is missing accessor '{1}'
CS0552	Error	'{0}': user-defined conversions to or from an interface are not allowed
CS0553	Error	'{0}': user-defined conversions to or from a base class are not allowed
CS0554	Error	'{0}': user-defined conversions to or from a derived class are not allowed
CS0555	Error	User-defined operator cannot take an object of the enclosing type and convert to an object of the enclosing type
CS0556	Error	User-defined conversion must convert to or from the enclosing type
CS0557	Error	Duplicate user-defined conversion in type '{0}'
CS0558	Error	User-defined operator '{0}' must be declared static and public
CS0559	Error	The parameter type for ++ or -- operator must be the containing type
CS0562	Error	The parameter of a unary operator must be the containing type
CS0563	Error	One of the parameters of a binary operator must be the containing type
CS0564	Error	The first operand of an overloaded shift operator must have the same type as the containing type, and the type of the second operand must be int
CS0567	Error	Interfaces cannot contain conversion, equality, or inequality operators
CS0568	Error	Structs cannot contain explicit parameterless constructors
CS0569	Error	'{0}': cannot override '{1}' because it is not supported by the language
CS0570	Error	'{0}' is not supported by the language
CS0571	Error	'{0}': cannot explicitly call operator or accessor
CS0572	Error	'{0}': cannot reference a type through an expression; try '{1}' instead
CS0573	Error	'{0}': cannot have instance property or field initializers in structs
CS0574	Error	Name of destructor must match name of class
CS0575	Error	Only class types can contain destructors
CS0576	Error	Namespace '{1}' contains a definition conflicting with alias '{0}'
CS0577	Error	The Conditional attribute is not valid on '{0}' because it is a constructor, destructor, operator, or explicit interface implementation
CS0578	Error	The Conditional attribute is not valid on '{0}' because its return type is not void
CS0579	Error	Duplicate '{0}' attribute
CS0582	Error	The Conditional attribute is not valid on interface members
CS0590	Error	User-defined operators cannot return void
CS0591	Error	Invalid value for argument to '{0}' attribute
CS0592	Error	Attribute '{0}' is not valid on this declaration type. It is only valid on '{1}' declarations.
CS0594	Error	Floating-point constant is outside the range of type '{0}'
CS0595	Error	Invalid real literal.
CS0596	Error	The Guid attribute must be specified with the ComImport attribute
CS0599	Error	Invalid value for named attribute argument '{0}'
CS0601	Error	The DllImport attribute must be specified on a method marked 'static' and 'extern'
CS0610	Error	Field or property cannot be of type '{0}'
CS0611	Error	Array elements cannot be of type '{0}'
CS0612	Warning	'{0}' is obsolete
CS0616	Error	'{0}' is not an attribute class
CS0617	Error	'{0}' is not a valid named attribute argument. Named attribute arguments must be fields which are not readonly, static, or const, or read-write properties which are public and not static.
CS0618	Warning	'{0}' is obsolete: '{1}'
CS0619	Error	'{0}' is obsolete: '{1}'
CS0620	Error	Indexers cannot have void type
CS0621	Error	'{0}': virtual or abstract members cannot be private
CS0622	Error	Can only use array initializer expressions to assign to array types. Try using a new expression instead.
CS0623	Error	Array initializers can only be used in a variable or field initializer. Try using a new expression instead.
CS0625	Error	'{0}': instance field in types marked with StructLayout(LayoutKind.Explicit) must have a FieldOffset attribute
CS0626	Warning	Method, operator, or accessor '{0}' is marked external and has no attributes on it. Consider adding a DllImport attribute to specify the external implementation.
CS0628	Warning	'{0}': new protected member declared in sealed class
CS0629	Error	Conditional member '{0}' cannot implement interface member '{1}' in type '{2}'
CS0630	Error	'{0}' cannot implement interface member '{1}' in type '{2}' because it has an __arglist parameter
CS0631	Error	ref and out are not valid in this context
CS0633	Error	The argument to the '{0}' attribute must be a valid identifier
CS0636	Error	The FieldOffset attribute can only be placed on members of types marked with the StructLayout(LayoutKind.Explicit)
CS0637	Error	The FieldOffset attribute is not allowed on static or const fields
CS0641	Error	Attribute '{0}' is only valid on classes derived from System.Attribute
CS0642	Warning	Possible mistaken empty statement
CS0643	Error	'{0}' duplicate named attribute argument
CS0644	Error	'{0}' cannot derive from special class '{1}'
CS0646	Error	Cannot specify the DefaultMember attribute on a type containing an indexer
CS0648	Error	'{0}' is a type not supported by the language
CS0649	Warning	Field '{0}' is never assigned to, and will always have its default value {1}
CS0650	Error	Bad array declarator: To declare a managed array the rank specifier precedes the variable's identifier. To declare a fixed size buffer field, use the fixed keyword before the field type.
CS0652	Warning	Comparison to integral constant is useless; the constant is outside the range of type '{0}'
CS0653	Error	Cannot apply attribute class '{0}' because it is abstract
CS0655	Error	'{0}' is not a valid named attribute argument because it is not a valid attribute parameter type
CS0656	Error	Missing compiler required member '{0}.{1}'
CS0657	Warning	'{0}' is not a valid attribute location for this declaration. Valid attribute locations for this declaration are '{1}'. All attributes in this block will be ignored.
CS0658	Warning	'{0}' is not a recognized attribute location. Valid attribute locations for this declaration are '{1}'. All attributes in this block will be ignored.
CS0659	Warning	'{0}' overrides Object.Equals(object o) but does not override Object.GetHashCode()
CS0660	Warning	'{0}' defines operator == or operator != but does not override Object.Equals(object o)
CS0661	Warning	'{0}' defines operator == or operator != but does not override Object.GetHashCode()
CS0662	Error	Cannot specify the Out attribute on a ref parameter without also specifying the In attribute.
CS0663	Error	'{0}' cannot define an overloaded {1} that differs only on parameter modifiers '{2}' and '{3}'
CS0664	Error	Literal of type double cannot be implicitly converted to type '{1}'; use an '{0}' suffix to create a literal of this type
CS0665	Warning	Assignment in conditional expression is always constant; did you mean to use == instead of = ?
CS0666	Error	'{0}': new protected member declared in struct
CS0668	Error	Two indexers have different names; the IndexerName attribute must be used with the same name on every indexer within a type
CS0669	Error	A class with the ComImport attribute cannot have a user-defined constructor
CS0670	Error	Field cannot have void type
CS0672	Warning	Member '{0}' overrides obsolete member '{1}'. Add the Obsolete attribute to '{0}'.
CS0673	Error	System.Void cannot be used from C# -- use typeof(void) to get the void type object
CS0674	Error	Do not use 'System.ParamArrayAttribute'. Use the 'params' keyword instead.
CS0675	Warning	Bitwise-or operator used on a sign-extended operand; consider casting to a smaller unsigned type first
CS0677	Error	'{0}': a volatile field cannot be of the type '{1}'
CS0678	Error	'{0}': a field cannot be both volatile and readonly
CS0681	Error	The modifier 'abstract' is not valid on fields. Try using a property instead.
CS0682	Error	'{0}' cannot implement '{1}' because it is not supported by the language
CS0683	Error	'{0}' explicit method implementation cannot implement '{1}' because it is an accessor
CS0684	Warning	'{0}' interface marked with 'CoClassAttribute' not marked with 'ComImportAttribute'
CS0685	Error	Conditional member '{0}' cannot have an out parameter
CS0686	Error	Accessor '{0}' cannot implement interface member '{1}' for type '{2}'. Use an explicit interface implementation.
CS0687	Error	The namespace alias qualifier '::' always resolves to a type or namespace so is illegal here. Consider using '.' instead.
CS0689	Error	Cannot derive from '{0}' because it is a type parameter
CS0692	Error	Duplicate type parameter '{0}'
CS0693	Warning	Type parameter '{0}' has the same name as the type parameter from outer type '{1}'
CS0694	Error	Type parameter '{0}' has the same name as the containing type, or method
CS0695	Error	'{0}' cannot implement both '{1}' and '{2}' because they may unify for some type parameter substitutions
CS0698	Error	A generic type cannot derive from '{0}' because it is an attribute class
CS0699	Error	'{1}' does not define type parameter '{0}'
CS0701	Error	'{0}' is not a valid constraint. A type used as a constraint must be an interface, a non-sealed class or a type parameter.
CS0702	Error	Constraint cannot be special class '{0}'
CS0703	Error	Inconsistent accessibility: constraint type '{1}' is less accessible than '{0}'
CS0704	Error	Cannot do member lookup in '{0}' because it is a type parameter
CS0706	Error	Invalid constraint type. A type used as a constraint must be an interface, a non-sealed class or a type parameter.
CS0708	Error	'{0}': cannot declare instance members in a static class
CS0709	Error	'{1}': cannot derive from static class '{0}'
CS0710	Error	Static classes cannot have instance constructors
CS0711	Error	Static classes cannot contain destructors
CS0712	Error	Cannot create an instance of the static class '{0}'
CS0713	Error	Static class '{0}' cannot derive from type '{1}'. Static classes must derive from object.
CS0714	Error	'{0}': static classes cannot implement interfaces
CS0715	Error	'{0}': static classes cannot contain user-defined operators
CS0716	Error	Cannot convert to static type '{0}'
CS0717	Error	'{0}': static classes cannot be used as constraints
CS0718	Error	'{0}': static types cannot be used as type arguments
CS0719	Error	'{0}': array elements cannot be of static type
CS0720	Error	'{0}': cannot declare indexers in a static class
CS0721	Error	'{0}': static types cannot be used as parameters
CS0722	Error	'{0}': static types cannot be used as return types
CS0723	Error	Cannot declare a variable of static type '{0}'
CS0724	Error	A throw statement with no arguments is not allowed in a finally clause that is nested inside the nearest enclosing catch clause
CS0726	Error	'{0}' is not a valid format specifier
CS0728	Warning	Possibly incorrect assignment to local '{0}' which is the argument to a using or lock statement. The Dispose call or unlocking will happen on the original value of the local.
CS0729	Error	Type '{0}' is defined in this assembly, but a type forwarder is specified for it
CS0730	Error	Cannot forward type '{0}' because it is a nested type of '{1}'
CS0731	Error	The type forwarder for type '{0}' in assembly '{1}' causes a cycle
CS0734	Error	The /moduleassemblyname option may only be specified when building a target type of 'module'
CS0735	Error	Invalid type specified as an argument for TypeForwardedTo attribute
CS0736	Error	'{0}' does not implement interface member '{1}'. '{2}' cannot implement an interface member because it is static.
CS0737	Error	'{0}' does not implement interface member '{1}'. '{2}' cannot implement an interface member because it is not public.
CS0738	Error	'{0}' does not implement interface member '{1}'. '{2}' cannot implement '{1}' because it does not have the matching return type of '{3}'.
CS0739	Error	'{0}' duplicate TypeForwardedToAttribute
CS0742	Error	A query body must end with a select clause or a group clause
CS0743	Error	Expected contextual keyword 'on'
CS0744	Error	Expected contextual keyword 'equals'
CS0745	Error	Expected contextual keyword 'by'
CS0746	Error	Invalid anonymous type member declarator. Anonymous type members must be declared with a member assignment, simple name or member access.
CS0747	Error	Invalid initializer member declarator
CS0748	Error	Inconsistent lambda parameter usage; parameter types must be all explicit or all implicit
CS0750	Error	A partial method cannot have access modifiers or the virtual, abstract, override, new, sealed, or extern modifiers
CS0751	Error	A partial method must be declared within a partial class, partial struct, or partial interface
CS0752	Error	A partial method cannot have out parameters
CS0754	Error	A partial method may not explicitly implement an interface method
CS0755	Error	Both partial method declarations must be extension methods or neither may be an extension method
CS0756	Error	A partial method may not have multiple defining declarations
CS0757	Error	A partial method may not have multiple implementing declarations
CS0758	Error	Both partial method declarations must use a params parameter or neither may use a params parameter
CS0759	Error	No defining declaration found for implementing declaration of partial method '{0}'
CS0761	Error	Partial method declarations of '{0}' have inconsistent constraints for type parameter '{1}'
CS0762	Error	Cannot create delegate from method '{0}' because it is a partial method without an implementing declaration
CS0763	Error	Both partial method declarations must be static or neither may be static
CS0764	Error	Both partial method declarations must be unsafe or neither may be unsafe
CS0765	Error	Partial methods with only a defining declaration or removed conditional methods cannot be used in expression trees
CS0766	Error	Partial methods must have a void return type
CS0767	Error	Cannot inherit interface '{0}' with the specified type parameters because it causes method '{1}' to contain overloads which differ only on ref and out
CS0768	Error	Constructor '{0}' cannot call itself through another constructor
CS0809	Warning	Obsolete member '{0}' overrides non-obsolete member '{1}'
CS0811	Warning	The fully qualified name for '{0}' is too long for debug information. Compile without '/debug' option.
CS0815	Error	Cannot assign {0} to an implicitly-typed variable
CS0818	Error	Implicitly-typed variables must be initialized
CS0819	Error	Implicitly-typed variables cannot have multiple declarators
CS0820	Error	Cannot initialize an implicitly-typed variable with an array initializer
CS0821	Error	Implicitly-typed local variables cannot be fixed
CS0822	Error	Implicitly-typed variables cannot be constant
CS0824	Warning	Constructor '{0}' is marked external
CS0825	Error	The contextual keyword 'var' may only appear within a local variable declaration or in script code
CS0826	Error	No best type found for implicitly-typed array
CS0828	Error	Cannot assign '{0}' to anonymous type property
CS0831	Error	An expression tree may not contain a base access
CS0832	Error	An expression tree may not contain an assignment operator
CS0833	Error	An anonymous type cannot have multiple properties with the same name
CS0834	Error	A lambda expression with a statement body cannot be converted to an expression tree
CS0835	Error	Cannot convert lambda to an expression tree whose type argument '{0}' is not a delegate type
CS0836	Error	Cannot use anonymous type in a constant expression
CS0837	Error	The first operand of an 'is' or 'as' operator may not be a lambda expression, anonymous method, or method group.
CS0838	Error	An expression tree may not contain a multidimensional array initializer
CS0839	Error	Argument missing
CS0841	Error	Cannot use local variable '{0}' before it is declared
CS0843	Error	Auto-implemented property '{0}' must be fully assigned before control is returned to the caller.
CS0844	Error	Cannot use local variable '{0}' before it is declared. The declaration of the local variable hides the field '{1}'.
CS0845	Error	An expression tree lambda may not contain a coalescing operator with a null or default literal left-hand side
CS0846	Error	A nested array initializer is expected
CS0847	Error	An array initializer of length '{0}' is expected
CS0853	Error	An expression tree may not contain a named argument specification
CS0854	Error	An expression tree may not contain a call or invocation that uses optional arguments
CS0855	Error	An expression tree may not contain an indexed property
CS0856	Error	Indexed property '{0}' has non-optional arguments which must be provided
CS0857	Error	Indexed property '{0}' must have all arguments optional
CS1001	Error	Identifier expected
CS1002	Error	; expected
CS1003	Error	Syntax error, '{0}' expected
CS1004	Error	Duplicate '{0}' modifier
CS1007	Error	Property accessor already defined
CS1008	Error	Type byte, sbyte, short, ushort, int, uint, long, or ulong expected
CS1009	Error	Unrecognized escape sequence
CS1010	Error	Newline in constant
CS1011	Error	Empty character literal
CS1012	Error	Too many characters in character literal
CS1013	Error	Invalid number
CS1014	Error	A get or set accessor expected
CS1015	Error	An object, string, or class type expected
CS1016	Error	Named attribute argument expected
CS1017	Error	Catch clauses cannot follow the general catch clause of a try statement
CS1018	Error	Keyword 'this' or 'base' expected
CS1019	Error	Overloadable unary operator expected
CS1020	Error	Overloadable binary operator expected
CS1021	Error	Integral constant is too large
CS1022	Error	Type or namespace definition, or end-of-file expected
CS1023	Error	Embedded statement cannot be a declaration or labeled statement
CS1024	Error	Preprocessor directive expected
CS1025	Error	Single-line comment or end-of-line expected
CS1026	Error	) expected
CS1027	Error	#endif directive expected
CS1028	Error	Unexpected preprocessor directive
CS1029	Error	#error: '{0}'
CS1030	Warning	#warning: '{0}'
CS1031	Error	Type expected
CS1032	Error	Cannot define/undefine preprocessor symbols after first token in file
CS1035	Error	End-of-file found, '*/' expected
CS1037	Error	Overloadable operator expected
CS1038	Error	#endregion directive expected
CS1039	Error	Unterminated string literal
CS1040	Error	Preprocessor directives must appear as the first non-whitespace character on a line
CS1041	Error	Identifier expected; '{1}' is a keyword
CS1043	Error	{ or ; expected
CS1044	Error	Cannot use more than one type in a for, using, fixed, or declaration statement
CS1055	Error	An add or remove accessor expected
CS1056	Error	Unexpected character '{0}'
CS1057	Error	'{0}': static classes cannot contain protected members
CS1058	Warning	A previous catch clause already catches all exceptions. All non-exceptions thrown will be wrapped in a System.Runtime.CompilerServices.RuntimeWrappedException.
CS1059	Error	The operand of an increment or decrement operator must be a variable, property or indexer
CS1061	Error	'{0}' does not contain a definition for '{1}' and no accessible extension method '{1}' accepting a first argument of type '{0}' could be found (are you missing a using directive or an assembly reference?)
CS1062	Warning	The best overloaded Add method '{0}' for the collection initializer element is obsolete. {1}
CS1063	Error	The best overloaded Add method '{0}' for the collection initializer element is obsolete. {1}
CS1064	Warning	The best overloaded Add method '{0}' for the collection initializer element is obsolete.
CS1065	Error	Default values are not valid in this context.
CS1066	Warning	The default value specified for parameter '{0}' will have no effect because it applies to a member that is used in contexts that do not allow optional arguments
CS1067	Error	Partial declarations of '{0}' must have the same type parameter names and variance modifiers in the same order
CS1068	Error	The type name '{0}' could not be found in the global namespace. This type has been forwarded to assembly '{1}' Consider adding a reference to that assembly.
CS1069	Error	The type name '{0}' could not be found in the namespace '{1}'. This type has been forwarded to assembly '{2}' Consider adding a reference to that assembly.
CS1070	Error	The type name '{0}' could not be found. This type has been forwarded to assembly '{1}'. Consider adding a reference to that assembly.
CS1072	Warning	Expected identifier or numeric literal.
CS1073	Error	Unexpected token '{0}'
CS1100	Error	Method '{0}' has a parameter modifier 'this' which is not on the first parameter
CS1103	Error	The first parameter of an extension method cannot be of type '{0}'
CS1104	Error	A parameter array cannot be used with 'this' modifier on an extension method
CS1105	Error	Extension method must be static
CS1106	Error	Extension method must be defined in a non-generic static class
CS1107	Error	A parameter can only have one '{0}' modifier
CS1109	Error	Extension methods must be defined in a top level static class; {0} is a nested class
CS1110	Error	Cannot define a new extension method because the compiler required type '{0}' cannot be found. Are you missing a reference to System.Core.dll?
CS1112	Error	Do not use 'System.Runtime.CompilerServices.ExtensionAttribute'. Use the 'this' keyword instead.
CS1113	Error	Extension method '{0}' defined on value type '{1}' cannot be used to create delegates
CS1501	Error	No overload for method '{0}' takes {1} arguments
CS1503	Error	Argument {0}: cannot convert from '{1}' to '{2}'
CS1504	Error	Source file '{0}' could not be opened -- {1}
CS1507	Error	Cannot link resource files when building a module
CS1508	Error	Resource identifier '{0}' has already been used in this assembly
CS1509	Error	The referenced file '{0}' is not an assembly
CS1510	Error	A ref or out value must be an assignable variable
CS1511	Error	Keyword 'base' is not available in a static method
CS1512	Error	Keyword 'base' is not available in the current context
CS1513	Error	} expected
CS1514	Error	{ expected
CS1515	Error	'in' expected
CS1517	Error	Invalid preprocessor expression
CS1519	Error	Invalid token '{0}' in class, struct, or interface member declaration
CS1520	Error	Method must have a return type
CS1521	Error	Invalid base type
CS1522	Warning	Empty switch block
CS1524	Error	Expected catch or finally
CS1525	Error	Invalid expression term '{0}'
CS1526	Error	A new expression requires (), [], or {} after type
CS1527	Error	Elements defined in a namespace cannot be explicitly declared as private, protected, protected internal, or private protected
CS1528	Error	Expected ; or = (cannot specify constructor arguments in declaration)
CS1529	Error	A using clause must precede all other elements defined in the namespace except extern alias declarations
CS1534	Error	Overloaded binary operator '{0}' takes two parameters
CS1535	Error	Overloaded unary operator '{0}' takes one parameter
CS1536	Error	Invalid parameter type 'void'
CS1537	Error	The using alias '{0}' appeared previously in this namespace
CS1540	Error	Cannot access protected member '{0}' via a qualifier of type '{1}'; the qualifier must be of type '{2}' (or derived from it)
CS1542	Error	'{0}' cannot be added to this assembly because it already is an assembly
CS1545	Error	Property, indexer, or event '{0}' is not supported by the language; try directly calling accessor methods '{1}' or '{2}'
CS1546	Error	Property, indexer, or event '{0}' is not supported by the language; try directly calling accessor method '{1}'
CS1547	Error	Keyword 'void' cannot be used in this context
CS1551	Error	Indexers must have at least one parameter
CS1552	Error	Array type specifier, [], must appear before parameter name
CS1553	Error	Declaration is not valid; use '{0} operator (...' instead
CS1555	Error	Could not find '{0}' specified for Main method
CS1556	Error	'{0}' specified for Main method must be a non-generic class, struct, or interface
CS1558	Error	'{0}' does not have a suitable static 'Main' method
CS1562	Error	Outputs without source must have the /out option specified
CS1564	Error	Conflicting options specified: Win32 resource file; Win32 manifest
CS1565	Error	Conflicting options specified: Win32 resource file; Win32 icon
CS1566	Error	Error reading resource '{0}' -- '{1}'
CS1569	Error	Error writing to XML documentation file: {0}
CS1570	Warning	XML comment has badly formed XML -- '{0}'
CS1571	Warning	XML comment has a duplicate param tag for '{0}'
CS1572	Warning	XML comment has a param tag for '{0}', but there is no parameter by that name
CS1573	Warning	Parameter '{0}' has no matching param tag in the XML comment for '{1}' (but other parameters do)
CS1574	Warning	XML comment has cref attribute '{0}' that could not be resolved
CS1575	Error	A stackalloc expression requires [] after type
CS1576	Error	The line number specified for #line directive is missing or invalid
CS1578	Error	Quoted file name, single-line comment or end-of-line expected
CS1579	Error	foreach statement cannot operate on variables of type '{0}' because '{0}' does not contain a public instance definition for '{1}'
CS1580	Warning	Invalid type for parameter {0} in XML comment cref attribute: '{1}'
CS1581	Warning	Invalid return type in XML comment cref attribute
CS1583	Error	Error reading Win32 resources -- {0}
CS1584	Warning	XML comment has syntactically incorrect cref attribute '{0}'
CS1585	Error	Member modifier '{0}' must precede the member type and name
CS1586	Error	Array creation must have array size or array initializer
CS1587	Warning	XML comment is not placed on a valid language element
CS1589	Warning	Unable to include XML fragment '{1}' of file '{0}' -- {2}
CS1590	Warning	Invalid XML include element -- {0}
CS1591	Warning	Missing XML comment for publicly visible type or member '{0}'
CS1592	Warning	Badly formed XML in included comments file -- '{0}'
CS1593	Error	Delegate '{0}' does not take {1} arguments
CS1597	Error	Semicolon after method or accessor block is not valid
CS1599	Error	Method or delegate cannot return type '{0}'
CS1600	Error	Compilation cancelled by user
CS1601	Error	Cannot make reference to variable of type '{0}'
CS1604	Error	Cannot assign to '{0}' because it is read-only
CS1605	Error	Cannot use '{0}' as a ref or out value because it is read-only
CS1607	Warning
CS1608	Error	The RequiredAttribute attribute is not permitted on C# types
CS1609	Error	Modifiers cannot be placed on event accessor declarations
CS1611	Error	The params parameter cannot be declared as {0}
CS1612	Error	Cannot modify the return value of '{0}' because it is not a variable
CS1613	Error	The managed coclass wrapper class '{0}' for interface '{1}' cannot be found (are you missing an assembly reference?)
CS1614	Error	'{0}' is ambiguous between '{1}' and '{2}'; use either '@{0}' or '{0}Attribute'
CS1615	Error	Argument {0} may not be passed with the '{1}' keyword
CS1616	Warning	Option '{0}' overrides attribute '{1}' given in a source file or added module
CS1617	Error	Invalid option '{0}' for /langversion. Use '/langversion:?' to list supported values.
CS1618	Error	Cannot create delegate with '{0}' because it or a method it overrides has a Conditional attribute
CS1619	Error	Cannot create temporary file -- {0}
CS1620	Error	Argument {0} must be passed with the '{1}' keyword
CS1621	Error	The yield statement cannot be used inside an anonymous method or lambda expression
CS1622	Error	Cannot return a value from an iterator. Use the yield return statement to return a value, or yield break to end the iteration.
CS1623	Error	Iterators cannot have ref, in or out parameters
CS1624	Error	The body of '{0}' cannot be an iterator block because '{1}' is not an iterator interface type
CS1625	Error	Cannot yield in the body of a finally clause
CS1626	Error	Cannot yield a value in the body of a try block with a catch clause
CS1627	Error	Expression expected after yield return
CS1628	Error	Cannot use ref, out, or in parameter '{0}' inside an anonymous method, lambda expression, query expression, or local function
CS1629	Error	Unsafe code may not appear in iterators
CS1631	Error	Cannot yield a value in the body of a catch clause
CS1632	Error	Control cannot leave the body of an anonymous method or lambda expression
CS1633	Warning	Unrecognized #pragma directive
CS1634	Warning	Expected disable, restore or enable
CS1635	Warning	Cannot restore warning 'CS{0}' because it was disabled globally
CS1636	Error	__arglist is not allowed in the parameter list of iterators
CS1637	Error	Iterators cannot have unsafe parameters or yield types
CS1639	Error	The managed coclass wrapper class signature '{0}' for interface '{1}' is not a valid class name signature
CS1640	Error	foreach statement cannot operate on variables of type '{0}' because it implements multiple instantiations of '{1}'; try casting to a specific interface instantiation
CS1641	Error	A fixed size buffer field must have the array size specifier after the field name
CS1642	Error	Fixed size buffer fields may only be members of structs
CS1643	Error	Not all code paths return a value in {0} of type '{1}'
CS1645	Warning	Feature '{0}' is not part of the standardized ISO C# language specification, and may not be accepted by other compilers
CS1646	Error	Keyword, identifier, or string expected after verbatim specifier: @
CS1648	Error	Members of readonly field '{0}' cannot be modified (except in a constructor or a variable initializer)
CS1649	Error	Members of readonly field '{0}' cannot be used as a ref or out value (except in a constructor)
CS1650	Error	Fields of static readonly field '{0}' cannot be assigned to (except in a static constructor or a variable initializer)
CS1651	Error	Fields of static readonly field '{0}' cannot be used as a ref or out value (except in a static constructor)
CS1654	Error	Cannot modify members of '{0}' because it is a '{1}'
CS1655	Error	Cannot use fields of '{0}' as a ref or out value because it is a '{1}'
CS1656	Error	Cannot assign to '{0}' because it is a '{1}'
CS1657	Error	Cannot use '{0}' as a ref or out value because it is a '{1}'
CS1658	Warning	{0}. See also error CS{1}.
CS1660	Error	Cannot convert {0} to type '{1}' because it is not a delegate type
CS1661	Error	Cannot convert {0} to type '{1}' because the parameter types do not match the delegate parameter types
CS1662	Error	Cannot convert {0} to intended delegate type because some of the return types in the block are not implicitly convertible to the delegate return type
CS1663	Error	Fixed size buffer type must be one of the following: bool, byte, short, int, long, char, sbyte, ushort, uint, ulong, float or double
CS1664	Error	Fixed size buffer of length {0} and type '{1}' is too big
CS1665	Error	Fixed size buffers must have a length greater than zero
CS1666	Error	You cannot use fixed size buffers contained in unfixed expressions. Try using the fixed statement.
CS1667	Error	Attribute '{0}' is not valid on property or event accessors. It is only valid on '{1}' declarations.
CS1668	Warning	Invalid search path '{0}' specified in '{1}' -- '{2}'
CS1669	Error	__arglist is not valid in this context
CS1670	Error	params is not valid in this context
CS1671	Error	A namespace declaration cannot have modifiers or attributes
CS1672	Error	Invalid option '{0}' for /platform; must be anycpu, x86, Itanium, arm, arm64 or x64
CS1673	Error	Anonymous methods, lambda expressions, and query expressions inside structs cannot access instance members of 'this'. Consider copying 'this' to a local variable outside the anonymous method, lambda expression or query expression and using the local instead.
CS1674	Error	'{0}': type used in a using statement must be implicitly convertible to 'System.IDisposable' or implement a suitable 'Dispose' method.
CS1676	Error	Parameter {0} must be declared with the '{1}' keyword
CS1677	Error	Parameter {0} should not be declared with the '{1}' keyword
CS1678	Error	Parameter {0} is declared as type '{1}{2}' but should be '{3}{4}'
CS1679	Error	Invalid extern alias for '/reference'; '{0}' is not a valid identifier
CS1680	Error	Invalid reference alias option: '{0}=' -- missing filename
CS1681	Error	You cannot redefine the global extern alias
CS1685	Warning	The predefined type '{0}' is defined in multiple assemblies in the global alias; using definition from '{1}'
CS1686	Error	Local '{0}' or its members cannot have their address taken and be used inside an anonymous method or lambda expression
CS1687	Warning	Source file has exceeded the limit of 16,707,565 lines representable in the PDB; debug information will be incorrect
CS1688	Error	Cannot convert anonymous method block without a parameter list to delegate type '{0}' because it has one or more out parameters
CS1689	Error	Attribute '{0}' is only valid on methods or attribute classes
CS1690	Warning	Accessing a member on '{0}' may cause a runtime exception because it is a field of a marshal-by-reference class
CS1692	Warning	Invalid number
CS1695	Warning	Invalid #pragma checksum syntax; should be #pragma checksum "filename" "{XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}" "XXXX..."
CS1696	Warning	Single-line comment or end-of-line expected
CS1697	Warning	Different checksum values given for '{0}'
CS1700	Warning	Assembly reference '{0}' is invalid and cannot be resolved
CS1701	Warning	Assuming assembly reference '{0}' used by '{1}' matches identity '{2}' of '{3}', you may need to supply runtime policy
CS1702	Warning	Assuming assembly reference '{0}' used by '{1}' matches identity '{2}' of '{3}', you may need to supply runtime policy
CS1703	Error	Multiple assemblies with equivalent identity have been imported: '{0}' and '{1}'. Remove one of the duplicate references.
CS1704	Error	An assembly with the same simple name '{0}' has already been imported. Try removing one of the references (e.g. '{1}') or sign them to enable side-by-side.
CS1705	Error	Assembly '{0}' with identity '{1}' uses '{2}' which has a higher version than referenced assembly '{3}' with identity '{4}'
CS1708	Error	Fixed size buffers can only be accessed through locals or fields
CS1710	Warning	XML comment has a duplicate typeparam tag for '{0}'
CS1711	Warning	XML comment has a typeparam tag for '{0}', but there is no type parameter by that name
CS1712	Warning	Type parameter '{0}' has no matching typeparam tag in the XML comment on '{1}' (but other type parameters do)
CS1715	Error	'{0}': type must be '{2}' to match overridden member '{1}'
CS1716	Error	Do not use 'System.Runtime.CompilerServices.FixedBuffer' attribute. Use the 'fixed' field modifier instead.
CS1717	Warning	Assignment made to same variable; did you mean to assign something else?
CS1718	Warning	Comparison made to same variable; did you mean to compare something else?
CS1719	Error	Error opening Win32 resource file '{0}' -- '{1}'
CS1720	Warning	Expression will always cause a System.NullReferenceException because the default value of '{0}' is null
CS1721	Error	Class '{0}' cannot have multiple base classes: '{1}' and '{2}'
CS1722	Error	Base class '{0}' must come before any interfaces
CS1723	Warning	XML comment has cref attribute '{0}' that refers to a type parameter
CS1725	Error	Friend assembly reference '{0}' is invalid. InternalsVisibleTo declarations cannot have a version, culture, public key token, or processor architecture specified.
CS1726	Error	Friend assembly reference '{0}' is invalid. Strong-name signed assemblies must specify a public key in their InternalsVisibleTo declarations.
CS1728	Error	Cannot bind delegate to '{0}' because it is a member of 'System.Nullable'
CS1729	Error	'{0}' does not contain a constructor that takes {1} arguments
CS1730	Error	Assembly and module attributes must precede all other elements defined in a file except using clauses and extern alias declarations
CS1733	Error	Expected expression
CS1734	Warning	XML comment on '{1}' has a paramref tag for '{0}', but there is no parameter by that name
CS1735	Warning	XML comment on '{1}' has a typeparamref tag for '{0}', but there is no type parameter by that name
CS1736	Error	Default parameter value for '{0}' must be a compile-time constant
CS1737	Error	Optional parameters must appear after all required parameters
CS1738	Error	Named argument specifications must appear after all fixed arguments have been specified. Please use language version {0} or greater to allow non-trailing named arguments.
CS1739	Error	The best overload for '{0}' does not have a parameter named '{1}'
CS1740	Error	Named argument '{0}' cannot be specified multiple times
CS1741	Error	A ref or out parameter cannot have a default value
CS1742	Error	An array access may not have a named argument specifier
CS1743	Error	Cannot specify a default value for the 'this' parameter
CS1744	Error	Named argument '{0}' specifies a parameter for which a positional argument has already been given
CS1745	Error	Cannot specify default parameter value in conjunction with DefaultParameterAttribute or OptionalAttribute
CS1746	Error	The delegate '{0}' does not have a parameter named '{1}'
CS1747	Error	Cannot embed interop types from assembly '{0}' because it is missing the '{1}' attribute.
CS1748	Error	Cannot find the interop type that matches the embedded interop type '{0}'. Are you missing an assembly reference?
CS1750	Error	A value of type '{0}' cannot be used as a default parameter because there are no standard conversions to type '{1}'
CS1751	Error	Cannot specify a default value for a parameter array
CS1752	Error	Interop type '{0}' cannot be embedded. Use the applicable interface instead.
CS1754	Error	Type '{0}' cannot be embedded because it is a nested type. Consider setting the 'Embed Interop Types' property to false.
CS1756	Error	Interop type '{0}' cannot be embedded because it is missing the required '{1}' attribute.
CS1757	Error	Embedded interop struct '{0}' can contain only public instance fields.
CS1758	Error	Cannot embed interop type '{0}' found in both assembly '{1}' and '{2}'. Consider setting the 'Embed Interop Types' property to false.
CS1759	Error	Cannot embed interop types from assembly '{0}' because it is missing either the '{1}' attribute or the '{2}' attribute.
CS1760	Error	Assemblies '{0}' and '{1}' refer to the same metadata but only one is a linked reference (specified using /link option); consider removing one of the references.
CS1761	Error	Embedding the interop type '{0}' from assembly '{1}' causes a name clash in the current assembly. Consider setting the 'Embed Interop Types' property to false.
CS1762	Warning	A reference was created to embedded interop assembly '{0}' because of an indirect reference to that assembly created by assembly '{1}'. Consider changing the 'Embed Interop Types' property on either assembly.
CS1763	Error	'{0}' is of type '{1}'. A default parameter value of a reference type other than string can only be initialized with null
CS1764	Error	Cannot use fixed local '{0}' inside an anonymous method, lambda expression, or query expression
CS1766	Error	Source interface '{0}' is missing method '{1}' which is required to embed event '{2}'.
CS1767	Error	Interface '{0}' has an invalid source interface which is required to embed event '{1}'.
CS1768	Error	Type '{0}' cannot be embedded because it has a generic argument. Consider setting the 'Embed Interop Types' property to false.
CS1769	Error	Type '{0}' from assembly '{1}' cannot be used across assembly boundaries because it has a generic type argument that is an embedded interop type.
CS1770	Error	A value of type '{0}' cannot be used as default parameter for nullable parameter '{1}' because '{0}' is not a simple type
CS1773	Error	Invalid version {0} for /subsystemversion. The version must be 6.02 or greater for ARM or AppContainerExe, and 4.00 or greater otherwise
CS1774	Error	Embedded interop method '{0}' contains a body.
CS1900	Error	Warning level must be in the range 0-4
CS1902	Error	Invalid option '{0}' for /debug; must be 'portable', 'embedded', 'full' or 'pdbonly'
CS1906	Error	Invalid option '{0}'; Resource visibility must be either 'public' or 'private'
CS1908	Error	The type of the argument to the DefaultParameterValue attribute must match the parameter type
CS1910	Error	Argument of type '{0}' is not applicable for the DefaultParameterValue attribute
CS1912	Error	Duplicate initialization of member '{0}'
CS1913	Error	Member '{0}' cannot be initialized. It is not a field or property.
CS1914	Error	Static field or property '{0}' cannot be assigned in an object initializer
CS1917	Error	Members of readonly field '{0}' of type '{1}' cannot be assigned with an object initializer because it is of a value type
CS1918	Error	Members of property '{0}' of type '{1}' cannot be assigned with an object initializer because it is of a value type
CS1919	Error	Unsafe type '{0}' cannot be used in object creation
CS1920	Error	Element initializer cannot be empty
CS1921	Error	The best overloaded method match for '{0}' has wrong signature for the initializer element. The initializable Add must be an accessible instance method.
CS1922	Error	Cannot initialize type '{0}' with a collection initializer because it does not implement 'System.Collections.IEnumerable'
CS1926	Error	Error opening Win32 manifest file {0} -- {1}
CS1927	Warning	Ignoring /win32manifest for module because it only applies to assemblies
CS1929	Error	'{0}' does not contain a definition for '{1}' and the best extension method overload '{2}' requires a receiver of type '{3}'
CS1930	Error	The range variable '{0}' has already been declared
CS1931	Error	The range variable '{0}' conflicts with a previous declaration of '{0}'
CS1932	Error	Cannot assign {0} to a range variable
CS1934	Error	Could not find an implementation of the query pattern for source type '{0}'. '{1}' not found. Consider explicitly specifying the type of the range variable '{2}'.
CS1935	Error	Could not find an implementation of the query pattern for source type '{0}'. '{1}' not found. Are you missing a reference to 'System.Core.dll' or a using directive for 'System.Linq'?
CS1936	Error	Could not find an implementation of the query pattern for source type '{0}'. '{1}' not found.
CS1937	Error	The name '{0}' is not in scope on the left side of 'equals'. Consider swapping the expressions on either side of 'equals'.
CS1938	Error	The name '{0}' is not in scope on the right side of 'equals'. Consider swapping the expressions on either side of 'equals'.
CS1939	Error	Cannot pass the range variable '{0}' as an out or ref parameter
CS1940	Error	Multiple implementations of the query pattern were found for source type '{0}'. Ambiguous call to '{1}'.
CS1941	Error	The type of one of the expressions in the {0} clause is incorrect. Type inference failed in the call to '{1}'.
CS1942	Error	The type of the expression in the {0} clause is incorrect. Type inference failed in the call to '{1}'.
CS1943	Error	An expression of type '{0}' is not allowed in a subsequent from clause in a query expression with source type '{1}'. Type inference failed in the call to '{2}'.
CS1944	Error	An expression tree may not contain an unsafe pointer operation
CS1945	Error	An expression tree may not contain an anonymous method expression
CS1946	Error	An anonymous method expression cannot be converted to an expression tree
CS1947	Error	Range variable '{0}' cannot be assigned to -- it is read only
CS1948	Error	The range variable '{0}' cannot have the same name as a method type parameter
CS1949	Error	The contextual keyword 'var' cannot be used in a range variable declaration
CS1950	Error	The best overloaded Add method '{0}' for the collection initializer has some invalid arguments
CS1951	Error	An expression tree lambda may not contain a ref, in or out parameter
CS1952	Error	An expression tree lambda may not contain a method with variable arguments
CS1954	Error	The best overloaded method match '{0}' for the collection initializer element cannot be used. Collection initializer 'Add' methods cannot have ref or out parameters.
CS1955	Error	Non-invocable member '{0}' cannot be used like a method.
CS1956	Warning	Member '{0}' implements interface member '{1}' in type '{2}'. There are multiple matches for the interface member at run-time. It is implementation dependent which method will be called.
CS1957	Warning	Member '{1}' overrides '{0}'. There are multiple override candidates at run-time. It is implementation dependent which method will be called.
CS1958	Error	Object and collection initializer expressions may not be applied to a delegate creation expression
CS1959	Error	'{0}' is of type '{1}'. The type specified in a constant declaration must be sbyte, byte, short, ushort, int, uint, long, ulong, char, float, double, decimal, bool, string, an enum-type, or a reference-type.
CS1960	Error	Invalid variance modifier. Only interface and delegate type parameters can be specified as variant.
CS1961	Error	Invalid variance: The type parameter '{1}' must be {3} valid on '{0}'. '{1}' is {2}.
CS1962	Error	The typeof operator cannot be used on the dynamic type
CS1963	Error	An expression tree may not contain a dynamic operation
CS1964	Error	'{0}': user-defined conversions to or from the dynamic type are not allowed
CS1965	Error	'{0}': cannot derive from the dynamic type
CS1966	Error	'{0}': cannot implement a dynamic interface '{1}'
CS1967	Error	Constraint cannot be the dynamic type
CS1968	Error	Constraint cannot be a dynamic type '{0}'
CS1969	Error	One or more types required to compile a dynamic expression cannot be found. Are you missing a reference?
CS1970	Error	Do not use 'System.Runtime.CompilerServices.DynamicAttribute'. Use the 'dynamic' keyword instead.
CS1971	Error	The call to method '{0}' needs to be dynamically dispatched, but cannot be because it is part of a base access expression. Consider casting the dynamic arguments or eliminating the base access.
CS1972	Error	The indexer access needs to be dynamically dispatched, but cannot be because it is part of a base access expression. Consider casting the dynamic arguments or eliminating the base access.
CS1973	Error	'{0}' has no applicable method named '{1}' but appears to have an extension method by that name. Extension methods cannot be dynamically dispatched. Consider casting the dynamic arguments or calling the extension method without the extension method syntax.
CS1974	Warning	The dynamically dispatched call to method '{0}' may fail at runtime because one or more applicable overloads are conditional methods.
CS1975	Error	The constructor call needs to be dynamically dispatched, but cannot be because it is part of a constructor initializer. Consider casting the dynamic arguments.
CS1976	Error	Cannot use a method group as an argument to a dynamically dispatched operation. Did you intend to invoke the method?
CS1977	Error	Cannot use a lambda expression as an argument to a dynamically dispatched operation without first casting it to a delegate or expression tree type.
CS1978	Error	Cannot use an expression of type '{0}' as an argument to a dynamically dispatched operation.
CS1979	Error	Query expressions over source type 'dynamic' or with a join sequence of type 'dynamic' are not allowed
CS1980	Error	Cannot define a class or member that utilizes 'dynamic' because the compiler required type '{0}' cannot be found. Are you missing a reference?
CS1981	Warning	Using '{0}' to test compatibility with '{1}' is essentially identical to testing compatibility with '{2}' and will succeed for all non-null values
CS1983	Error	The return type of an async method must be void, Task, Task, a task-like type, IAsyncEnumerable, or IAsyncEnumerator
CS1984	Error	Cannot await in the body of a finally clause
CS1985	Error	Cannot await in a catch clause
CS1986	Error	'await' requires that the type {0} have a suitable 'GetAwaiter' method
CS1988	Error	Async methods cannot have ref, in or out parameters
CS1989	Error	Async lambda expressions cannot be converted to expression trees
CS1991	Error	'{0}' cannot implement '{1}' because '{2}' is a Windows Runtime event and '{3}' is a regular .NET event.
CS1992	Error	The 'await' operator can only be used when contained within a method or lambda expression marked with the 'async' modifier
CS1994	Error	The 'async' modifier can only be used in methods that have a body.
CS1995	Error	The 'await' operator may only be used in a query expression within the first collection expression of the initial 'from' clause or within the collection expression of a 'join' clause
CS1996	Error	Cannot await in the body of a lock statement
CS1997	Error	Since '{0}' is an async method that returns 'Task', a return keyword must not be followed by an object expression. Did you intend to return 'Task'?
CS1998	Warning	This async method lacks 'await' operators and will run synchronously. Consider using the 'await' operator to await non-blocking API calls, or 'await Task.Run(...)' to do CPU-bound work on a background thread.
CS2001	Error	Source file '{0}' could not be found.
CS2002	Warning	Source file '{0}' specified multiple times
CS2005	Error	Missing file specification for '{0}' option
CS2006	Error	Command-line syntax error: Missing '{0}' for '{1}' option
CS2007	Error	Unrecognized option: '{0}'
CS2008	Warning	No source files specified.
CS2011	Error	Error opening response file '{0}'
CS2012	Error	Cannot open '{0}' for writing -- '{1}'
CS2013	Error	Invalid image base number '{0}'
CS2015	Error	'{0}' is a binary file instead of a text file
CS2016	Fatal	Code page '{0}' is invalid or not installed
CS2017	Error	Cannot specify /main if building a module or library
CS2019	Fatal	Invalid target type for /target: must specify 'exe', 'winexe', 'library', or 'module'
CS2021	Fatal	File name '{0}' is empty, contains invalid characters, has a drive specification without an absolute path, or is too long
CS2023	Warning	Ignoring /noconfig option because it was specified in a response file
CS2024	Error	Invalid file section alignment '{0}'
CS2029	Warning	Invalid name for a preprocessing symbol; '{0}' is not a valid identifier
CS2033	Fatal	Cannot create short filename '{0}' when a long filename with the same short filename already exists
CS2034	Error	A /reference option that declares an extern alias can only have one filename. To specify multiple aliases or filenames, use multiple /reference options.
CS2035	Error	Command-line syntax error: Missing ':' for '{0}' option
CS2036	Error	The /pdb option requires that the /debug option also be used
CS2037	Error	An expression tree lambda may not contain a COM call with ref omitted on arguments
CS2038	Warning	The language name '{0}' is invalid.
CS2039	Error	Command-line syntax error: Invalid Guid format '{0}' for option '{1}'
CS2040	Error	Command-line syntax error: Missing Guid for option '{1}'
CS2041	Error	Invalid output name: {0}
CS2042	Error	Invalid debug information format: {0}
CS2043	Error	'id#' syntax is no longer supported. Use '$id' instead.
CS2044	Error	/sourcelink switch is only supported when emitting PDB.
CS2045	Error	/embed switch is only supported when emitting a PDB.
CS3000	Warning	Methods with variable arguments are not CLS-compliant
CS3001	Warning	Argument type '{0}' is not CLS-compliant
CS3002	Warning	Return type of '{0}' is not CLS-compliant
CS3003	Warning	Type of '{0}' is not CLS-compliant
CS3005	Warning	Identifier '{0}' differing only in case is not CLS-compliant
CS3006	Warning	Overloaded method '{0}' differing only in ref or out, or in array rank, is not CLS-compliant
CS3007	Warning	Overloaded method '{0}' differing only by unnamed array types is not CLS-compliant
CS3008	Warning	Identifier '{0}' is not CLS-compliant
CS3009	Warning	'{0}': base type '{1}' is not CLS-compliant
CS3010	Warning	'{0}': CLS-compliant interfaces must have only CLS-compliant members
CS3011	Warning	'{0}': only CLS-compliant members can be abstract
CS3012	Warning	You must specify the CLSCompliant attribute on the assembly, not the module, to enable CLS compliance checking
CS3013	Warning	Added modules must be marked with the CLSCompliant attribute to match the assembly
CS3014	Warning	'{0}' cannot be marked as CLS-compliant because the assembly does not have a CLSCompliant attribute
CS3015	Warning	'{0}' has no accessible constructors which use only CLS-compliant types
CS3016	Warning	Arrays as attribute arguments is not CLS-compliant
CS3017	Warning	You cannot specify the CLSCompliant attribute on a module that differs from the CLSCompliant attribute on the assembly
CS3018	Warning	'{0}' cannot be marked as CLS-compliant because it is a member of non-CLS-compliant type '{1}'
CS3019	Warning	CLS compliance checking will not be performed on '{0}' because it is not visible from outside this assembly
CS3021	Warning	'{0}' does not need a CLSCompliant attribute because the assembly does not have a CLSCompliant attribute
CS3022	Warning	CLSCompliant attribute has no meaning when applied to parameters. Try putting it on the method instead.
CS3023	Warning	CLSCompliant attribute has no meaning when applied to return types. Try putting it on the method instead.
CS3024	Warning	Constraint type '{0}' is not CLS-compliant
CS3026	Warning	CLS-compliant field '{0}' cannot be volatile
CS3027	Warning	'{0}' is not CLS-compliant because base interface '{1}' is not CLS-compliant
CS3028	Fatal	Algorithm '{0}' is not supported
CS4001	Error	Cannot await '{0}'
CS4003	Error	'await' cannot be used as an identifier within an async method or lambda expression
CS4004	Error	Cannot await in an unsafe context
CS4005	Error	Async methods cannot have unsafe parameters or return types
CS4006	Error	__arglist is not allowed in the parameter list of async methods
CS4007	Error	'await' cannot be used in an expression containing the type '{0}'
CS4008	Error	Cannot await 'void'
CS4009	Error	A void or int returning entry point cannot be async
CS4010	Error	Cannot convert async {0} to delegate type '{1}'. An async {0} may return void, Task or Task, none of which are convertible to '{1}'.
CS4011	Error	'await' requires that the return type '{0}' of '{1}.GetAwaiter()' have suitable 'IsCompleted', 'OnCompleted', and 'GetResult' members, and implement 'INotifyCompletion' or 'ICriticalNotifyCompletion'
CS4012	Error	Parameters or locals of type '{0}' cannot be declared in async methods or lambda expressions.
CS4013	Error	Instance of type '{0}' cannot be used inside a nested function, query expression, iterator block or async method
CS4014	Warning	Because this call is not awaited, execution of the current method continues before the call is completed. Consider applying the 'await' operator to the result of the call.
CS4015	Error	'MethodImplOptions.Synchronized' cannot be applied to an async method
CS4016	Error	Since this is an async method, the return expression must be of type '{0}' rather than 'Task<{0}>'
CS4017	Error	CallerLineNumberAttribute cannot be applied because there are no standard conversions from type '{0}' to type '{1}'
CS4018	Error	CallerFilePathAttribute cannot be applied because there are no standard conversions from type '{0}' to type '{1}'
CS4019	Error	CallerMemberNameAttribute cannot be applied because there are no standard conversions from type '{0}' to type '{1}'
CS4020	Error	The CallerLineNumberAttribute may only be applied to parameters with default values
CS4021	Error	The CallerFilePathAttribute may only be applied to parameters with default values
CS4022	Error	The CallerMemberNameAttribute may only be applied to parameters with default values
CS4023	Error	/platform:anycpu32bitpreferred can only be used with /t:exe, /t:winexe and /t:appcontainerexe
CS4024	Warning	The CallerLineNumberAttribute applied to parameter '{0}' will have no effect because it applies to a member that is used in contexts that do not allow optional arguments
CS4025	Warning	The CallerFilePathAttribute applied to parameter '{0}' will have no effect because it applies to a member that is used in contexts that do not allow optional arguments
CS4026	Warning	The CallerMemberNameAttribute applied to parameter '{0}' will have no effect because it applies to a member that is used in contexts that do not allow optional arguments
CS4027	Error	'{0}' does not implement '{1}'
CS4028	Error	'await' requires that the type '{0}' have a suitable 'GetAwaiter' method. Are you missing a using directive for 'System'?
CS4029	Error	Cannot return an expression of type 'void'
CS4030	Error	Security attribute '{0}' cannot be applied to an Async method.
CS4031	Error	Async methods are not allowed in an Interface, Class, or Structure which has the 'SecurityCritical' or 'SecuritySafeCritical' attribute.
CS4032	Error	The 'await' operator can only be used within an async method. Consider marking this method with the 'async' modifier and changing its return type to 'Task<{0}>'.
CS4033	Error	The 'await' operator can only be used within an async method. Consider marking this method with the 'async' modifier and changing its return type to 'Task'.
CS4034	Error	The 'await' operator can only be used within an async {0}. Consider marking this {0} with the 'async' modifier.
CS4036	Error	'{0}' does not contain a definition for '{1}' and no extension method '{1}' accepting a first argument of type '{0}' could be found (are you missing a using directive for '{2}'?)
CS5001	Error	Program does not contain a static 'Main' method suitable for an entry point
CS7000	Error	Unexpected use of an aliased name
CS7002	Error	Unexpected use of a generic name
CS7003	Error	Unexpected use of an unbound generic name
CS7006	Error	Expressions and statements can only occur in a method body
CS7007	Error	A 'using static' directive can only be applied to types; '{0}' is a namespace not a type. Consider a 'using namespace' directive instead
CS7008	Error	The assembly name '{0}' is reserved and cannot be used as a reference in an interactive session
CS7009	Error	Cannot use #r after first token in file
CS7010	Error	Quoted file name expected
CS7011	Error	#r is only allowed in scripts
CS7012	Error	The name '{0}' does not exist in the current context (are you missing a reference to assembly '{1}'?)
CS7013	Error	Name '{0}' exceeds the maximum length allowed in metadata.
CS7014	Error	Attributes are not valid in this context.
CS7015	Error	'extern alias' is not valid in this context
CS7016	Error	Alias '{0}' conflicts with {1} definition
CS7017	Error	Member definition, statement, or end-of-file expected
CS7018	Error	Expected a script (.csx file) but none specified
CS7019	Error	Type of '{0}' cannot be inferred since its initializer directly or indirectly refers to the definition.
CS7020	Error	Cannot use 'yield' in top-level script code
CS7021	Error	Cannot declare namespace in script code
CS7022	Warning	The entry point of the program is global script code; ignoring '{0}' entry point.
CS7023	Error	The second operand of an 'is' or 'as' operator may not be static type '{0}'
CS7024	Error	Delegate '{0}' has no invoke method or an invoke method with a return type or parameter types that are not supported.
CS7025	Error	Inconsistent accessibility: event type '{1}' is less accessible than event '{0}'
CS7026	Error	Assembly and module attributes are not allowed in this context
CS7027	Error	Error signing output with public key from file '{0}' -- {1}
CS7028	Error	Error signing output with public key from container '{0}' -- {1}
CS7029	Error	Friend access was granted by '{0}', but the strong name signing state of the output assembly does not match that of the granting assembly.
CS7030	Error	Cannot pass null for friend assembly name
CS7032	Error	Key file '{0}' is missing the private key needed for signing
CS7033	Warning	Delay signing was specified and requires a public key, but no public key was specified
CS7034	Error	The specified version string does not conform to the required format - major[.minor[.build[.revision]]]
CS7035	Warning	The specified version string does not conform to the recommended format - major.minor.build.revision
CS7036	Error	There is no argument given that corresponds to the required formal parameter '{0}' of '{1}'
CS7038	Error	Failed to emit module '{0}'.
CS7041	Error	Each linked resource and module must have a unique filename. Filename '{0}' is specified more than once in this assembly
CS7042	Error	The DllImport attribute cannot be applied to a method that is generic or contained in a generic type.
CS7043	Error	Cannot update '{0}'; attribute '{1}' is missing.
CS7045	Error	Parameter not valid for the specified unmanaged type.
CS7046	Error	Attribute parameter '{0}' must be specified.
CS7047	Error	Attribute parameter '{0}' or '{1}' must be specified.
CS7048	Error	First argument to a security attribute must be a valid SecurityAction
CS7049	Error	Security attribute '{0}' has an invalid SecurityAction value '{1}'
CS7050	Error	SecurityAction value '{0}' is invalid for security attributes applied to an assembly
CS7051	Error	SecurityAction value '{0}' is invalid for security attributes applied to a type or a method
CS7052	Error	SecurityAction value '{0}' is invalid for PrincipalPermission attribute
CS7053	Error	An expression tree may not contain '{0}'
CS7054	Error	Unmanaged type '{0}' not valid for fields.
CS7055	Error	Unmanaged type '{0}' is only valid for fields.
CS7056	Error	Unable to resolve file path '{0}' specified for the named argument '{1}' for PermissionSet attribute
CS7057	Error	Error reading file '{0}' specified for the named argument '{1}' for PermissionSet attribute: '{2}'
CS7058	Error	The specified version string does not conform to the required format - major.minor.build.revision (without wildcards)
CS7059	Error	Executables cannot be satellite assemblies; culture should always be empty
CS7061	Error	Duplicate '{0}' attribute in '{1}'
CS7064	Error	Error opening icon file {0} -- {1}
CS7065	Error	Error building Win32 resources -- {0}
CS7066	Error	Yield statements may not appear at the top level in interactive code.
CS7067	Error	Attribute constructor parameter '{0}' is optional, but no default parameter value was specified.
CS7068	Error	Reference to type '{0}' claims it is defined in this assembly, but it is not defined in source or any added modules
CS7069	Error	Reference to type '{0}' claims it is defined in '{1}', but it could not be found
CS7070	Error	Security attribute '{0}' is not valid on this declaration type. Security attributes are only valid on assembly, type and method declarations.
CS7071	Error	Assembly reference '{0}' is invalid and cannot be resolved
CS7079	Error	The type '{0}' is defined in a module that has not been added. You must add the module '{1}'.
CS7080	Warning	The CallerMemberNameAttribute applied to parameter '{0}' will have no effect. It is overridden by the CallerFilePathAttribute.
CS7081	Warning	The CallerMemberNameAttribute applied to parameter '{0}' will have no effect. It is overridden by the CallerLineNumberAttribute.
CS7082	Warning	The CallerFilePathAttribute applied to parameter '{0}' will have no effect. It is overridden by the CallerLineNumberAttribute.
CS7083	Error	Expression must be implicitly convertible to Boolean or its type '{0}' must define operator '{1}'.
CS7084	Error	A Windows Runtime event may not be passed as an out or ref parameter.
CS7085	Error	By-reference return type 'ref {0}' is not supported.
CS7086	Error	Module name '{0}' stored in '{1}' must match its filename.
CS7087	Error	Invalid module name: {0}
CS7088	Error	Invalid '{0}' value: '{1}'.
CS7089	Error	AppConfigPath must be absolute.
CS7090	Warning	Attribute '{0}' from module '{1}' will be ignored in favor of the instance appearing in source
CS7091	Error	Attribute '{0}' given in a source file conflicts with option '{1}'.
CS7092	Error	A fixed buffer may only have one dimension.
CS7093	Error	Cannot read config file '{0}' -- '{1}'
CS7094	Error	Cannot await in the filter expression of a catch clause
CS7095	Warning	Filter expression is a constant 'true', consider removing the filter
CS7096	Error	Cannot continue since the edit includes a reference to an embedded type: '{0}'.
CS7098	Error	Linked netmodule metadata must provide a full PE image: '{0}'.
CS7099	Error	Metadata references are not supported.
CS7100	Error	Assembly culture strings may not contain embedded NUL characters.
CS7101	Error	Member '{0}' added during the current debug session can only be accessed from within its declaring assembly '{1}'.
CS7102	Error	Compilation options '{0}' and '{1}' can't both be specified at the same time.
CS7103	Error	Unable to read debug information of method '{0}' (token 0x{1:X8}) from assembly '{2}'
CS8001	Warning	The command line switch '{0}' is not yet implemented and was ignored.
CS8002	Warning	Referenced assembly '{0}' does not have a strong name.
CS8003	Error	Invalid signature public key specified in AssemblySignatureKeyAttribute.
CS8004	Error	Type '{0}' exported from module '{1}' conflicts with type declared in primary module of this assembly.
CS8005	Error	Type '{0}' exported from module '{1}' conflicts with type '{2}' exported from module '{3}'.
CS8006	Error	Forwarded type '{0}' conflicts with type declared in primary module of this assembly.
CS8007	Error	Type '{0}' forwarded to assembly '{1}' conflicts with type '{2}' forwarded to assembly '{3}'.
CS8008	Error	Type '{0}' forwarded to assembly '{1}' conflicts with type '{2}' exported from module '{3}'.
CS8009	Warning	Referenced assembly '{0}' has different culture setting of '{1}'.
CS8010	Error	Agnostic assembly cannot have a processor specific module '{0}'.
CS8011	Error	Assembly and module '{0}' cannot target different processors.
CS8012	Warning	Referenced assembly '{0}' targets a different processor.
CS8013	Error	Cryptographic failure while creating hashes.
CS8014	Error	Reference to '{0}' netmodule missing.
CS8015	Error	Module '{0}' is already defined in this assembly. Each module must have a unique filename.
CS8016	Error	Transparent identifier member access failed for field '{0}' of '{1}'. Does the data being queried implement the query pattern?
CS8017	Error	The parameter has multiple distinct default values.
CS8018	Warning	Within cref attributes, nested types of generic types should be qualified.
CS8019	Hidden	Unnecessary using directive.
CS8020	Hidden	Unused extern alias.
CS8021	Warning	No value for RuntimeMetadataVersion found. No assembly containing System.Object was found nor was a value for RuntimeMetadataVersion specified through options.
CS8022	Error	Feature '{0}' is not available in C# 1. Please use language version {1} or greater.
CS8023	Error	Feature '{0}' is not available in C# 2. Please use language version {1} or greater.
CS8024	Error	Feature '{0}' is not available in C# 3. Please use language version {1} or greater.
CS8025	Error	Feature '{0}' is not available in C# 4. Please use language version {1} or greater.
CS8026	Error	Feature '{0}' is not available in C# 5. Please use language version {1} or greater.
CS8027	Error	The field has multiple distinct constant values.
CS8028	Error	'{0}': a class with the ComImport attribute cannot specify field initializers.
CS8029	Warning	Local name '{0}' is too long for PDB. Consider shortening or compiling without /debug.
CS8030	Error	Anonymous function converted to a void returning delegate cannot return a value
CS8031	Error	Async lambda expression converted to a 'Task' returning delegate cannot return a value. Did you intend to return 'Task'?
CS8032	Warning	An instance of analyzer {0} cannot be created from {1} : {2}.
CS8033	Warning	The assembly {0} does not contain any analyzers.
CS8034	Warning	Unable to load Analyzer assembly {0} : {1}
CS8035	Error	Error reading ruleset file {0} - {1}
CS8036	Error	Error reading debug information for '{0}'
CS8040	Info	Skipping some types in analyzer assembly {0} due to a ReflectionTypeLoadException : {1}.
CS8050	Error	Only auto-implemented properties can have initializers.
CS8051	Error	Auto-implemented properties must have get accessors.
CS8054	Error	Enums cannot contain explicit parameterless constructors
CS8055	Error	Cannot emit debug information for a source text without encoding.
CS8057	Error	Block bodies and expression bodies cannot both be provided.
CS8058	Error	Feature '{0}' is experimental and unsupported; use '/features:{1}' to enable.
CS8059	Error	Feature '{0}' is not available in C# 6. Please use language version {1} or greater.
CS8070	Error	Control cannot fall out of switch from final case label ('{0}')
CS8072	Error	An expression tree lambda may not contain a null propagating operator.
CS8073	Warning	The result of the expression is always '{0}' since a value of type '{1}' is never equal to 'null' of type '{2}'
CS8074	Error	An expression tree lambda may not contain a dictionary initializer.
CS8075	Error	An extension Add method is not supported for a collection initializer in an expression lambda.
CS8076	Error	Missing close delimiter '}' for interpolated expression started with '{'.
CS8077	Error	A single-line comment may not be used in an interpolated string.
CS8078	Error	An expression is too long or complex to compile
CS8079	Error	Use of possibly unassigned auto-implemented property '{0}'
CS8080	Error	Auto-implemented properties must override all accessors of the overridden property.
CS8081	Error	Expression does not have a name.
CS8082	Error	Sub-expression cannot be used in an argument to nameof.
CS8083	Error	An alias-qualified name is not an expression.
CS8084	Error	Type parameters are not allowed on a method group as an argument to 'nameof'.
CS8085	Error	A 'using static' directive cannot be used to declare an alias
CS8086	Error	A '{0}' character must be escaped (by doubling) in an interpolated string.
CS8087	Error	A '{0}' character may only be escaped by doubling '{0}{0}' in an interpolated string.
CS8088	Error	A format specifier may not contain trailing whitespace.
CS8089	Error	Empty format specifier.
CS8090	Error	There is an error in a referenced assembly '{0}'.
CS8091	Error	'{0}' cannot be extern and have a constructor initializer
CS8092	Error	Expression or declaration statement expected.
CS8093	Error	Extension method groups are not allowed as an argument to 'nameof'.
CS8094	Warning	Alignment value {0} has a magnitude greater than {1} and may result in a large formatted string.
CS8095	Error	Length of String constant exceeds current memory limit. Try splitting the string into multiple constants.
CS8096	Error	Debug entry point must be a definition of a method declared in the current compilation.
CS8097	Error	#load is only allowed in scripts
CS8098	Error	Cannot use #load after first token in file
CS8099	Error	Source file references are not supported.
CS8100	Error	The 'await' operator cannot be used in a static script variable initializer.
CS8101	Error	The pathmap option was incorrectly formatted.
CS8102	Error	Public signing was specified and requires a public key, but no public key was specified.
CS8103	Error	Combined length of user strings used by the program exceeds allowed limit. Try to decrease use of string literals.
CS8104	Error	An error occurred while writing the output file: {0}.
CS8105	Warning	Attribute '{0}' is ignored when public signing is specified.
CS8106	Error	Option '{0}' must be an absolute path.
CS8107	Error	Feature '{0}' is not available in C# 7.0. Please use language version {1} or greater.
CS8108	Error	Cannot pass argument with dynamic type to params parameter '{0}' of local function '{1}'.
CS8110	Error	An expression tree may not contain a reference to a local function
CS8111	Error	Invalid instrumentation kind: {0}
CS8112	Error	'{0}' is a local function and must therefore always have a body.
CS8113	Error	Invalid hash algorithm name: '{0}'
CS8115	Error	A throw expression is not allowed in this context.
CS8116	Error	It is not legal to use nullable type '{0}' in a pattern; use the underlying type '{1}' instead.
CS8117	Error	Invalid operand for pattern match; value required, but found '{0}'.
CS8119	Error	The switch expression must be a value; found '{0}'.
CS8120	Error	The switch case has already been handled by a previous case.
CS8121	Error	An expression of type '{0}' cannot be handled by a pattern of type '{1}'.
CS8122	Error	An expression tree may not contain an 'is' pattern-matching operator.
CS8123	Warning	The tuple element name '{0}' is ignored because a different name or no name is specified by the target type '{1}'.
CS8124	Error	Tuple must contain at least two elements.
CS8125	Error	Tuple element name '{0}' is only allowed at position {1}.
CS8126	Error	Tuple element name '{0}' is disallowed at any position.
CS8127	Error	Tuple element names must be unique.
CS8128	Error	Member '{0}' was not found on type '{1}' from assembly '{2}'.
CS8129	Error	No suitable 'Deconstruct' instance or extension method was found for type '{0}', with {1} out parameters and a void return type.
CS8130	Error	Cannot infer the type of implicitly-typed deconstruction variable '{0}'.
CS8131	Error	Deconstruct assignment requires an expression with a type on the right-hand-side.
CS8132	Error	Cannot deconstruct a tuple of '{0}' elements into '{1}' variables.
CS8133	Error	Cannot deconstruct dynamic objects.
CS8134	Error	Deconstruction must contain at least two variables.
CS8135	Error	Tuple with {0} elements cannot be converted to type '{1}'.
CS8136	Error	Deconstruction 'var (...)' form disallows a specific type for 'var'.
CS8137	Error	Cannot define a class or member that utilizes tuples because the compiler required type '{0}' cannot be found. Are you missing a reference?
CS8138	Error	Cannot reference 'System.Runtime.CompilerServices.TupleElementNamesAttribute' explicitly. Use the tuple syntax to define tuple names.
CS8139	Error	'{0}': cannot change tuple element names when overriding inherited member '{1}'
CS8140	Error	'{0}' is already listed in the interface list on type '{2}' with different tuple element names, as '{1}'.
CS8141	Error	The tuple element names in the signature of method '{0}' must match the tuple element names of interface method '{1}' (including on the return type).
CS8142	Error	Both partial method declarations, '{0}' and '{1}', must use the same tuple element names.
CS8143	Error	An expression tree may not contain a tuple literal.
CS8144	Error	An expression tree may not contain a tuple conversion.
CS8145	Error	Auto-implemented properties cannot return by reference
CS8146	Error	Properties which return by reference must have a get accessor
CS8147	Error	Properties which return by reference cannot have set accessors
CS8148	Error	'{0}' must match by reference return of overridden member '{1}'
CS8149	Error	By-reference returns may only be used in methods that return by reference
CS8150	Error	By-value returns may only be used in methods that return by value
CS8151	Error	The return expression must be of type '{0}' because this method returns by reference
CS8152	Error	'{0}' does not implement interface member '{1}'. '{2}' cannot implement '{1}' because it does not have matching return by reference.
CS8153	Error	An expression tree lambda may not contain a call to a method, property, or indexer that returns by reference
CS8154	Error	The body of '{0}' cannot be an iterator block because '{0}' returns by reference
CS8155	Error	Lambda expressions that return by reference cannot be converted to expression trees
CS8156	Error	An expression cannot be used in this context because it may not be passed or returned by reference
CS8157	Error	Cannot return '{0}' by reference because it was initialized to a value that cannot be returned by reference
CS8158	Error	Cannot return by reference a member of '{0}' because it was initialized to a value that cannot be returned by reference
CS8159	Error	Cannot return the range variable '{0}' by reference
CS8160	Error	A readonly field cannot be returned by writable reference
CS8161	Error	A static readonly field cannot be returned by writable reference
CS8162	Error	Members of readonly field '{0}' cannot be returned by writable reference
CS8163	Error	Fields of static readonly field '{0}' cannot be returned by writable reference
CS8166	Error	Cannot return a parameter by reference '{0}' because it is not a ref or out parameter
CS8167	Error	Cannot return by reference a member of parameter '{0}' because it is not a ref or out parameter
CS8168	Error	Cannot return local '{0}' by reference because it is not a ref local
CS8169	Error	Cannot return a member of local '{0}' by reference because it is not a ref local
CS8170	Error	Struct members cannot return 'this' or other instance members by reference
CS8171	Error	Cannot initialize a by-value variable with a reference
CS8172	Error	Cannot initialize a by-reference variable with a value
CS8173	Error	The expression must be of type '{0}' because it is being assigned by reference
CS8174	Error	A declaration of a by-reference variable must have an initializer
CS8175	Error	Cannot use ref local '{0}' inside an anonymous method, lambda expression, or query expression
CS8176	Error	Iterators cannot have by-reference locals
CS8177	Error	Async methods cannot have by-reference locals
CS8178	Error	'await' cannot be used in an expression containing a call to '{0}' because it returns by reference
CS8179	Error	Predefined type '{0}' is not defined or imported
CS8180	Error	{ or ; or => expected
CS8181	Error	'new' cannot be used with tuple type. Use a tuple literal expression instead.
CS8182	Error	Predefined type '{0}' must be a struct.
CS8183	Error	Cannot infer the type of implicitly-typed discard.
CS8184	Error	A deconstruction cannot mix declarations and expressions on the left-hand-side.
CS8185	Error	A declaration is not allowed in this context.
CS8186	Error	A foreach loop must declare its iteration variables.
CS8187	Error	Tuple element names are not permitted on the left of a deconstruction.
CS8188	Error	An expression tree may not contain a throw-expression.
CS8189	Error	Ref mismatch between '{0}' and delegate '{1}'
CS8190	Error	Provided source code kind is unsupported or invalid: '{0}'
CS8191	Error	Provided documentation mode is unsupported or invalid: '{0}'.
CS8192	Error	Provided language version is unsupported or invalid: '{0}'.
CS8196	Error	Reference to an implicitly-typed out variable '{0}' is not permitted in the same argument list.
CS8197	Error	Cannot infer the type of implicitly-typed out variable '{0}'.
CS8198	Error	An expression tree may not contain an out argument variable declaration.
CS8199	Error	The syntax 'var (...)' as an lvalue is reserved.
CS8202	Error	Public signing is not supported for netmodules.
CS8203	Error	Invalid assembly name: {0}
CS8204	Error	For type '{0}' to be used as an AsyncMethodBuilder for type '{1}', its Task property should return type '{1}' instead of type '{2}'.
CS8205	Error	Attributes are not allowed on local function parameters or type parameters
CS8206	Error	Module '{0}' in assembly '{1}' is forwarding the type '{2}' to multiple assemblies: '{3}' and '{4}'.
CS8207	Error	An expression tree may not contain a discard.
CS8208	Error	It is not legal to use the type 'dynamic' in a pattern.
CS8209	Error	A value of type 'void' may not be assigned.
CS8210	Error	A tuple may not contain a value of type 'void'.
CS8300	Error	Merge conflict marker encountered
CS8301	Error	Invalid name for a preprocessing symbol; '{0}' is not a valid identifier
CS8302	Error	Feature '{0}' is not available in C# 7.1. Please use language version {1} or greater.
CS8303	Error	Specified language version '{0}' cannot have leading zeroes
CS8304	Error	Compiler version: '{0}'. Language version: {1}.
CS8305	Warning	'{0}' is for evaluation purposes only and is subject to change or removal in future updates.
CS8306	Error	Tuple element name '{0}' is inferred. Please use language version {1} or greater to access an element by its inferred name.
CS8307	Error	The first operand of an 'as' operator may not be a tuple literal without a natural type.
CS8308	Error	Do not use refout when using refonly.
CS8309	Error	Cannot compile net modules when using /refout or /refonly.
CS8310	Error	Operator '{0}' cannot be applied to operand '{1}'
CS8311	Error	Cannot use a default literal as an argument to a dynamically dispatched operation.
CS8312	Error	Use of default literal is not valid in this context
CS8313	Error	A default literal 'default' is not valid as a case constant. Use another literal (e.g. '0' or 'null') as appropriate. If you intended to write the default label, use 'default:' without 'case'.
CS8314	Error	An expression of type '{0}' cannot be handled by a pattern of type '{1}' in C# {2}. Please use language version {3} or greater.
CS8315	Error	Operator '{0}' is ambiguous on operands 'default' and 'default'
CS8320	Error	Feature '{0}' is not available in C# 7.2. Please use language version {1} or greater.
CS8321	Warning	The local function '{0}' is declared but never used
CS8322	Error	Cannot pass argument with dynamic type to generic local function '{0}' with inferred type arguments.
CS8323	Error	Named argument '{0}' is used out-of-position but is followed by an unnamed argument
CS8324	Error	Named argument specifications must appear after all fixed arguments have been specified in a dynamic invocation.
CS8325	Error	'await' cannot be used in an expression containing a ref conditional operator
CS8326	Error	Both conditional operator values must be ref values or neither may be a ref value
CS8327	Error	The expression must be of type '{0}' to match the alternative ref value
CS8328	Error	The parameter modifier '{0}' cannot be used with '{1}'
CS8329	Error	Cannot use {0} '{1}' as a ref or out value because it is a readonly variable
CS8330	Error	Members of {0} '{1}' cannot be used as a ref or out value because it is a readonly variable
CS8331	Error	Cannot assign to {0} '{1}' because it is a readonly variable
CS8332	Error	Cannot assign to a member of {0} '{1}' because it is a readonly variable
CS8333	Error	Cannot return {0} '{1}' by writable reference because it is a readonly variable
CS8334	Error	Members of {0} '{1}' cannot be returned by writable reference because it is a readonly variable
CS8335	Error	Do not use '{0}'. This is reserved for compiler usage.
CS8336	Error	The type name '{0}' is reserved to be used by the compiler.
CS8337	Error	The first parameter of a 'ref' extension method '{0}' must be a value type or a generic type constrained to struct.
CS8338	Error	The first parameter of the 'in' extension method '{0}' must be a concrete (non-generic) value type.
CS8340	Error	Instance fields of readonly structs must be readonly.
CS8341	Error	Auto-implemented instance properties in readonly structs must be readonly.
CS8342	Error	Field-like events are not allowed in readonly structs.
CS8343	Error	'{0}': ref structs cannot implement interfaces
CS8344	Error	foreach statement cannot operate on enumerators of type '{0}' in async or iterator methods because '{0}' is a ref struct.
CS8345	Error	Field or auto-implemented property cannot be of type '{0}' unless it is an instance member of a ref struct.
CS8346	Error	Conversion of a stackalloc expression of type '{0}' to type '{1}' is not possible.
CS8347	Error	Cannot use a result of '{0}' in this context because it may expose variables referenced by parameter '{1}' outside of their declaration scope
CS8348	Error	Cannot use a member of result of '{0}' in this context because it may expose variables referenced by parameter '{1}' outside of their declaration scope
CS8349	Error	Expression cannot be used in this context because it may indirectly expose variables outside of their declaration scope
CS8350	Error	This combination of arguments to '{0}' is disallowed because it may expose variables referenced by parameter '{1}' outside of their declaration scope
CS8351	Error	Branches of a ref conditional operator cannot refer to variables with incompatible declaration scopes
CS8352	Error	Cannot use local '{0}' in this context because it may expose referenced variables outside of their declaration scope
CS8353	Error	A result of a stackalloc expression of type '{0}' cannot be used in this context because it may be exposed outside of the containing method
CS8354	Error	Cannot return 'this' by reference.
CS8355	Error	An in parameter cannot have the Out attribute.
CS8356	Error	Predefined type '{0}' is declared in multiple referenced assemblies: '{1}' and '{2}'
CS8357	Error	The specified version string contains wildcards, which are not compatible with determinism. Either remove wildcards from the version string, or disable determinism for this compilation
CS8358	Error	Cannot use attribute constructor '{0}' because it is has 'in' parameters.
CS8359	Warning	Filter expression is a constant 'false', consider removing the catch clause
CS8360	Warning	Filter expression is a constant 'false', consider removing the try-catch block
CS8361	Error	A conditional expression cannot be used directly in a string interpolation because the ':' ends the interpolation. Parenthesize the conditional expression.
CS8362	Error	__arglist cannot have an argument of void type
CS8364	Error	Arguments with 'in' modifier cannot be used in dynamically dispatched expressions.
CS8370	Error	Feature '{0}' is not available in C# 7.3. Please use language version {1} or greater.
CS8371	Warning	Field-targeted attributes on auto-properties are not supported in language version {0}. Please use language version {1} or greater.
CS8372	Error	Do not use 'System.Runtime.CompilerServices.FixedBuffer' attribute on a property
CS8373	Error	The left-hand side of a ref assignment must be a ref local or parameter.
CS8374	Error	Cannot ref-assign '{1}' to '{0}' because '{1}' has a narrower escape scope than '{0}'.
CS8375	Error	The 'new()' constraint cannot be used with the 'unmanaged' constraint
CS8376	Error	The 'unmanaged' constraint must come before any other constraints
CS8377	Error	The type '{2}' must be a non-nullable value type, along with all fields at any level of nesting, in order to use it as parameter '{1}' in the generic type or method '{0}'
CS8378	Error	__arglist cannot have an argument passed by 'in' or 'out'
CS8379	Error	Type parameter '{1}' has the 'unmanaged' constraint so '{1}' cannot be used as a constraint for '{0}'
CS8380	Error	'{0}': cannot specify both a constraint class and the 'unmanaged' constraint
CS8381	Error	"Invalid rank specifier: expected ']'
CS8382	Error	An expression tree may not contain a tuple == or != operator
CS8383	Warning	The tuple element name '{0}' is ignored because a different name or no name is specified on the other side of the tuple == or != operator.
CS8384	Error	Tuple types used as operands of an == or != operator must have matching cardinalities. But this operator has tuple types of cardinality {0} on the left and {1} on the right.
CS8385	Error	The given expression cannot be used in a fixed statement
CS8386	Error	Invalid object creation
CS8387	Warning	Type parameter '{0}' has the same name as the type parameter from outer method '{1}'
CS8388	Error	An out variable cannot be declared as a ref local
CS8400	Error	Feature '{0}' is not available in C# 8.0. Please use language version {1} or greater.
CS8401	Error	To use '@$' instead of '$@' for an interpolated verbatim string, please use language version '{0}' or greater.
CS8402	Warning	'default' is converted to 'null', not 'default({0})'
CS8403	Error	Method '{0}' with an iterator block must be 'async' to return '{1}'
CS8410	Error	'{0}': type used in an async using statement must be implicitly convertible to 'System.IAsyncDisposable' or implement a suitable 'DisposeAsync' method.
CS8411	Error	Asynchronous foreach statement cannot operate on variables of type '{0}' because '{0}' does not contain a suitable public instance definition for '{1}'
CS8412	Error	Asynchronous foreach requires that the return type '{0}' of '{1}' must have a suitable public 'MoveNextAsync' method and public 'Current' property
CS8413	Error	Asynchronous foreach statement cannot operate on variables of type '{0}' because it implements multiple instantiations of '{1}'; try casting to a specific interface instantiation
CS8414	Error	foreach statement cannot operate on variables of type '{0}' because '{0}' does not contain a public instance definition for '{1}'. Did you mean 'await foreach' rather than 'foreach'?
CS8415	Error	Asynchronous foreach statement cannot operate on variables of type '{0}' because '{0}' does not contain a public instance definition for '{1}'. Did you mean 'foreach' rather than 'await foreach'?
CS8416	Error	Cannot use a collection of dynamic type in an asynchronous foreach
CS8417	Error	'{0}': type used in an async using statement must be implicitly convertible to 'System.IAsyncDisposable' or implement a suitable 'DisposeAsync' method. Did you mean 'using' rather than 'await using'?
CS8418	Error	'{0}': type used in a using statement must be implicitly convertible to 'System.IDisposable' or implement a suitable 'Dispose' method. Did you mean 'await using' rather than 'using'?
CS8419	Error	The body of an async-iterator method must contain a 'yield' statement.
CS8420	Error	The body of an async-iterator method must contain a 'yield' statement. Consider removing 'async' from the method declaration or adding a 'yield' statement.
CS8421	Error	A static local function cannot contain a reference to '{0}'.
CS8422	Error	A static local function cannot contain a reference to 'this' or 'base'.
CS8423	Error	Attribute '{0}' is not valid on event accessors. It is only valid on '{1}' declarations.
CS8424	Warning	The EnumeratorCancellationAttribute applied to parameter '{0}' will have no effect. The attribute is only effective on a parameter of type CancellationToken in an async-iterator method returning IAsyncEnumerable
CS8425	Warning	Async-iterator '{0}' has one or more parameters of type 'CancellationToken' but none of them is decorated with the 'EnumeratorCancellation' attribute, so the cancellation token parameter from the generated 'IAsyncEnumerable<>.GetAsyncEnumerator' will be unconsumed
CS8426	Error	The attribute [EnumeratorCancellation] cannot be used on multiple parameters
CS8502	Error	Matching the tuple type '{0}' requires '{1}' subpatterns, but '{2}' subpatterns are present.
CS8503	Error	A property subpattern requires a reference to the property or field to be matched, e.g. '{{ Name: {0} }}'
CS8504	Error	Pattern missing
CS8505	Error	A default literal 'default' is not valid as a pattern. Use another literal (e.g. '0' or 'null') as appropriate. To match everything, use a discard pattern '_'.
CS8506	Error	No best type was found for the switch expression.
CS8507	Error	A single-element deconstruct pattern requires some other syntax for disambiguation. It is recommended to add a discard designator '_' after the close paren ')'.
CS8508	Error	The syntax 'var' for a pattern is not permitted to refer to a type, but '{0}' is in scope here.
CS8509	Warning	The switch expression does not handle all possible inputs (it is not exhaustive).
CS8510	Error	The pattern has already been handled by a previous arm of the switch expression.
CS8511	Error	An expression of type '{0}' cannot be handled by a pattern of type '{1}'. Please use language version '{2}' or greater to match an open type with a constant pattern.
CS8512	Warning	The name '_' refers to the constant, not the discard pattern. Use 'var ' to discard the value, or '@' to refer to a constant by that name.
CS8513	Warning	The name '' refers to the type '{0}', not the discard pattern. Use '@' for the type, or 'var _' to discard.
CS8514	Error	An expression tree may not contain a switch expression.
CS8515	Error	Parentheses are required around the switch governing expression.
CS8516	Error	The name '{0}' does not identify tuple element '{1}'.
CS8517	Error	The name '{0}' does not match the corresponding 'Deconstruct' parameter '{1}'.
CS8518	Error	An expression of type '{0}' can never match the provided pattern.
CS8519	Warning	The given expression never matches the provided pattern.
CS8520	Warning	The given expression always matches the provided constant.
CS8521	Error	Pattern-matching is not permitted for pointer types.
CS8522	Error	Element names are not permitted when pattern-matching via 'System.Runtime.CompilerServices.ITuple'.
CS8523	Error	The discard pattern is not permitted as a case label in a switch statement. Use 'case var :' for a discard pattern, or 'case @:' for a constant named '_'.
CS8597	Warning	Thrown value may be null.
CS8598	Error	The suppression operator is not allowed in this context
CS8600	Warning	Converting null literal or possible null value to non-nullable type.
CS8601	Warning	Possible null reference assignment.
CS8602	Warning	Dereference of a possibly null reference.
CS8603	Warning	Possible null reference return.
CS8604	Warning	Possible null reference argument for parameter '{0}' in '{1}'.
CS8605	Warning	Unboxing a possibly null value.
CS8606	Warning	Possible null reference assignment to iteration variable
CS8607	Warning	A possible null value may not be passed to a target marked with the [DisallowNull] attribute
CS8609	Warning	Nullability of reference types in return type doesn't match overridden member.
CS8610	Warning	Nullability of reference types in type of parameter '{0}' doesn't match overridden member.
CS8611	Warning	Nullability of reference types in type of parameter '{0}' doesn't match partial method declaration.
CS8612	Warning	Nullability of reference types in type doesn't match implicitly implemented member '{0}'.
CS8613	Warning	Nullability of reference types in return type doesn't match implicitly implemented member '{0}'.
CS8614	Warning	Nullability of reference types in type of parameter '{0}' doesn't match implicitly implemented member '{1}'.
CS8615	Warning	Nullability of reference types in type doesn't match implemented member '{0}'.
CS8616	Warning	Nullability of reference types in return type doesn't match implemented member '{0}'.
CS8617	Warning	Nullability of reference types in type of parameter '{0}' doesn't match implemented member '{1}'.
CS8618	Warning	Non-nullable {0} '{1}' is uninitialized.
CS8619	Warning	Nullability of reference types in value of type '{0}' doesn't match target type '{1}'.
CS8620	Warning	Argument of type '{0}' cannot be used for parameter '{2}' of type '{1}' in '{3}' due to differences in the nullability of reference types.
CS8621	Warning	Nullability of reference types in return type of '{0}' doesn't match the target delegate '{1}'.
CS8622	Warning	Nullability of reference types in type of parameter '{0}' of '{1}' doesn't match the target delegate '{2}'.
CS8623	Error	Explicit application of 'System.Runtime.CompilerServices.NullableAttribute' is not allowed.
CS8624	Warning	Argument of type '{0}' cannot be used as an output of type '{1}' for parameter '{2}' in '{3}' due to differences in the nullability of reference types.
CS8625	Warning	Cannot convert null literal to non-nullable reference type.
CS8626	Warning	The 'as' operator may produce a null value when '{0}' is a non-nullable reference type.
CS8627	Error	A nullable type parameter must be known to be a value type or non-nullable reference type. Consider adding a 'class', 'struct', or type constraint.
CS8628	Error	Cannot use a nullable reference type in object creation.
CS8629	Warning	Nullable value type may be null.
CS8630	Error	Invalid '{0}' value: '{1}' for C# {2}. Please use language version '{3}' or greater.
CS8631	Warning	The type '{3}' cannot be used as type parameter '{2}' in the generic type or method '{0}'. Nullability of type argument '{3}' doesn't match constraint type '{1}'.
CS8632	Warning	The annotation for nullable reference types should only be used in code within a '#nullable' context.
CS8633	Warning	Nullability in constraints for type parameter '{0}' of method '{1}' doesn't match the constraints for type parameter '{2}' of interface method '{3}'. Consider using an explicit interface implementation instead.
CS8634	Warning	The type '{2}' cannot be used as type parameter '{1}' in the generic type or method '{0}'. Nullability of type argument '{2}' doesn't match 'class' constraint.
CS8635	Error	Unexpected character sequence '...'
CS8636	Error	Invalid option '{0}' for /nullable; must be 'disable', 'enable' or 'warnings'
CS8637	Error	Expected 'enable', 'disable', or 'restore'
CS8638	Warning	Conditional access may produce a null value when '{0}' is a non-nullable reference type.
CS8639	Error	The typeof operator cannot be used on a nullable reference type
CS8640	Error	Expression tree cannot contain value of ref struct or restricted type '{0}'.
CS8641	Error	'else' cannot start a statement.
CS8642	Error	An expression tree may not contain a null coalescing assignment
CS8643	Warning	Nullability of reference types in explicit interface specifier doesn't match interface implemented by the type.
CS8644	Warning	'{0}' does not implement interface member '{1}'. Nullability of reference types in interface implemented by the base type doesn't match.
CS8645	Warning	'{0}' is already listed in the interface list on type '{1}' with different nullability of reference types.
CS8646	Error	'{0}' is explicitly implemented more than once.
CS8647	Error	A using variable cannot be used directly within a switch section (consider using braces).
CS8648	Error	A goto cannot jump to a location after a using declaration.
CS8649	Error	A goto cannot jump to a location before a using declaration within the same block.
CS8650	Error	It is not legal to use nullable reference type '{0}?' in an is-type expression; use the underlying type '{0}' instead.
CS8651	Error	It is not legal to use nullable reference type '{0}?' in an as expression; use the underlying type '{0}' instead.
CS8652	Error	The feature '{0}' is currently in Preview and unsupported. To use Preview features, use the 'preview' language version.
CS8653	Warning	A default expression introduces a null value when '{0}' is a non-nullable reference type.
CS8654	Warning	A null literal introduces a null value when '{0}' is a non-nullable reference type.
CS8655	Warning	The switch expression does not handle some null inputs (it is not exhaustive).
CS8656	Warning	Call to non-readonly member '{0}' from a 'readonly' member results in an implicit copy of '{1}'.
CS8657	Error	Static member '{0}' cannot be marked 'readonly'.
CS8658	Error	Auto-implemented 'set' accessor '{0}' cannot be marked 'readonly'.
CS8659	Error	Auto-implemented property '{0}' cannot be marked 'readonly' because it has a 'set' accessor.
CS8660	Error	Cannot specify 'readonly' modifiers on both property or indexer '{0}' and its accessor. Remove one of them.
CS8661	Error	Cannot specify 'readonly' modifiers on both accessors of property or indexer '{0}'. Instead, put a 'readonly' modifier on the property itself.
CS8662	Error	Field-like event '{0}' cannot be 'readonly'.
CS8663	Error	Both partial method declarations must be readonly or neither may be readonly
CS8664	Error	'{0}': 'readonly' can only be used on accessors if the property or indexer has both a get and a set accessor
CS8665	Error	Method '{0}' specifies a 'class' constraint for type parameter '{1}', but corresponding type parameter '{2}' of overridden or explicitly implemented method '{3}' is not a reference type.
CS8666	Error	Method '{0}' specifies a 'struct' constraint for type parameter '{1}', but corresponding type parameter '{2}' of overridden or explicitly implemented method '{3}' is not a non-nullable value type.
CS8667	Warning	Partial method declarations of '{0}' have inconsistent nullability in constraints for type parameter '{1}'
CS8700	Error	Multiple analyzer config files cannot be in the same directory ('{0}').
CS8701	Error	Target runtime doesn't support default interface implementation.
CS8702	Error	'{0}' cannot implement interface member '{1}' in type '{2}' because the target runtime doesn't support default interface implementation.
CS8703	Error	The modifier '{0}' is not valid for this item in C# {1}. Please use language version '{2}' or greater.
CS8704	Error	'{0}' does not implement interface member '{1}'. '{2}' cannot implicitly implement a non-public member.
CS8705	Error	Interface member '{0}' does not have a most specific implementation. Neither '{1}', nor '{2}' are most specific.
CS8706	Error	'{0}' cannot implement interface member '{1}' in type '{2}' because feature '{3}' is not available in C# {4}. Please use language version '{5}' or greater.
CS8707	Error	Target runtime doesn't support 'protected', 'protected internal', or 'private protected' accessibility for a member of an interface.
CS8711	Error	Type '{0}' cannot be embedded because it has a non-abstract member. Consider setting the 'Embed Interop Types' property to false.
CS8712	Error	'{0}': abstract event cannot use event accessor syntax
CS8713	Error	The 'notnull' constraint must come before any other constraints
CS8714	Warning	The type '{2}' cannot be used as type parameter '{1}' in the generic type or method '{0}'. Nullability of type argument '{2}' doesn't match 'notnull' constraint.

Statistics

Severity	Count
Fatal	7
Error	1177
Warning	223
Info	1
Hidden	2
Total	1412

ahmad-moussawi/CSharpErrorsAndWarnings.md

All C# errors and warnings

Statistics