run this in the Package Manager Console:
Update-Package Microsoft.CodeDom.Providers.DotNetCompilerPlatform -r
This problem is not related to Visual Studio itself, so answers suggesting adding build steps to copy files over are rather a workaround. Same with adding compiler binaries manually to the project.
The Roslyn compiler comes from a NuGet package and there is/was a bug in some versions of that package (I don’t know exactly which ones). The solution is to reinstall/upgrade that package to a bug-free version. Originally before I wrote the answer back in 2015 I fixed it by installing following packages at specific versions:
- Microsoft.Net.Compilers 1.1.1
- Microsoft.CodeDom.Providers.DotNetCompilerPlatform 1.0.1
Then I looked into .csproj and made sure that the paths to packages are correct (in my case ..\..\packages\*.*) inside tags
<ImportProject> on top and in
<Target> with name “EnsureNuGetPackageBuildImports” on the bottom. This is on MVC 5 and .NET Framework 4.5.2.