I have a c# solution with the following structure:
mySolution
myProject
myProject.MSTests
References
Microsoft.VisualStudio.QualityTools.UnitTe
Another idea for the Googlers out there. My problem was trying to get ignored tests running again. Same MS error message occurs if you remove the Ignore label. Does not automatically re-enable the test. This article takes you through the last step. http://richallen.blogspot.com/2008/05/ms-test-re-enabling-ignored-tests.html