Ao executar o comando(c:/Windows/Microsoft.NET/Framework/v4.0.30319/csc.exe "Meu primeiro Programa.txt") no cmd aparece isso (Microsoft (R) Visual C# Compiler version 4.7.3056.0 for C# 5 Copyright (C) Microsoft Corporation. All rights reserved.
This compiler is provided as part of the Microsoft (R) .NET Framework, but only supports language versions up to C# 5, which is no longer the latest version. For compilers that support newer versions of the C# programming language, see http://go.microsoft.com/fwlink/?LinkID=533240 ).
Creio que seja para atualiza a versao do c# so que abri o link e vai para uma pagina no github e sou novato nao entendi nada alguem pode ajudar a resolver?