Nuget mess

Nuget issues

PM> install-package entityframework
'EntityFramework 6.1.3' already installed.
Adding 'EntityFramework 6.1.3' to Tests.
install-package : Failed to add reference to 'System.ComponentModel.DataAnnotations'. Please make sure that it is in the Global Assembly Cache.
At line:1 char:1
+ install-package entityframework
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [Install-Package], InvalidOperationException
    + FullyQualifiedErrorId : NuGetCmdletUnhandledException,NuGet.PowerShell.Commands.InstallPackageCommand
 
PM> 

// or this one: 
Package Manager Console Host Version 2.8.60723.765

Type 'get-help NuGet' to see all available NuGet commands.

PM> install-package entityframework
Installing 'EntityFramework 6.1.3'.
You are downloading EntityFramework from Microsoft, the license agreement to which is available at http://go.microsoft.com/fwlink/?LinkID=320539. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device.
Successfully installed 'EntityFramework 6.1.3'.
Adding 'EntityFramework 6.1.3' to Northwind.Adapter.Persistence.
Successfully added 'EntityFramework 6.1.3' to Northwind.Adapter.Persistence.
Uninstalling 'EntityFramework 6.1.3'.
Successfully uninstalled 'EntityFramework 6.1.3'.
Install failed. Rolling back...
install-package : Unable to cast object of type 'System.__ComObject' to type 'EnvDTE.Project'.
At line:1 char:1
+ install-package entityframework
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [Install-Package], InvalidCastException
    + FullyQualifiedErrorId : NuGetCmdletUnhandledException,NuGet.PowerShell.Commands.InstallPackageCommand
 
PM> install-package entityframework
Installing 'EntityFramework 6.1.3'.
You are downloading EntityFramework from Microsoft, the license agreement to which is available at http://go.microsoft.com/fwlink/?LinkID=320539. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device.
Successfully installed 'EntityFramework 6.1.3'.
Adding 'EntityFramework 6.1.3' to Northwind.Adapter.Persistence.
Successfully added 'EntityFramework 6.1.3' to Northwind.Adapter.Persistence

// i.e repeating the same thing ... works!

// Repeating the first issue takes 30 seconds! and then it succeeds. !!