Attempting to create new DB unit test in Visual Studio 2013 errors with "Error Member not found" DISP_E_MEMBERNOTFOUND

I have a test harness with three unit test projects. I have been actively creating tests and modifying expected results. Suddenly trying to create a unit test results in the error:

Member not found. (Exception from HRESULT: 0x80020003 (DISP_E_MEMBERNOTFOUND))

I create a unit test by right-clicking the stored procedure. In that pop-up box it does not matter if I choose an existing project or try to create a new project. They all produce the same error.

All tests can be run and/or modified. It is just impacting the creation of a new unit test. I have closed visual studio and re-opened project.

Any ideas?