A project won't compile because of a missing assembly. The file that causes the error has a 

using Microsoft.VisualStudio.DebuggerVisualizers;

The VisualStudio part is marked in red. What do I have to install to fix it? To me it sounds like something that would have come with Visual Studio, but that is what I am using, so it is installed...

Clarification: I know what assembly it exists in, and the reference is added earlier to the project references. But how do I get it? What SDK do I have to install? Or have I forgotten to check something off when I installed Visual Studio?

c# visual-studio assembly-resolution
Edit
Report