Track explicitly all application dependencies, verify them before letting the business to go wrong

AppDependencies.cs

public class AppDependencies
{
    public static void AreAllSatisfied()
    {
        IsValidConnectionString();
        IoC.AllTheTypesAreResolvable();

        var appConfig = IoC.Resolve<IAppConfig>();
        AssertDirectoryExists(appConfig.Logs);
        AssertDirectoryExists(appConfig.Assets);
        AssertDirectoryExists(appConfig.Temp);

        IsFtpConfigured();
    }

    private static void IsFtpConfigured()
    {
        try{
            var ftpProxy = IoC.Resolve<IFtpProxy>();
            ftpProxy.GetFiles(@"\");
        }
        catch (Exception e){
            throw new InvalidOperationException("The Ftp configuration is invalid.", e);
        }
    }

    private static void AssertDirectoryExists(string path)
    {
        if (Directory.Exists(path) == false)
            throw new InvalidOperationException(string.Format("The directory for '{0}' path does not exist.", path));
    }

    private static void IsValidConnectionString()
    {
        try{
            using (SqlConnection conn = FluentCommandConnectionFactory.GetConnection()){
                // this will force to get a open connection
            }
        }
        catch (Exception e){
            throw new InvalidOperationException("The connection string is invalid.", e);
        }
    }
}