How to run Roslyn instead csc.exe from command line?

Question

After installing VS 2015, running csc.exe from command line causes this message to be displayed to console:

This compiler is provided as part of the M

Answer 1

It sounds like your path is inappropriate, basically. If you open the "Developer Command Prompt for VS2015" you should have $ProgramFiles(x86)$\MSBuild\14.0\bin early in your path - and the csc.exe in there is Roslyn.

I suspect you're running the version in c:\Windows\Microsoft.NET\Framework\4.0.30319 or similar - which is the legacy one, basically.