The associated test case is not included in Visual Studio
2 answers
I had the same problem ("Link to Test Case" disabled) due to using MSTest V2 in my project (default in VS 2017).
To enable "Link to Test Case" simply change MSTest V2 to MSTest V1 in your project links:
MSTest V2: Microsoft.VisualStudio.TestPlatform.TestFramework
MSTest V1: Microsoft.VisualStudio.QualityTools.UnitTestFramework
+1
source to share