I'm running into this problem quite frequently. Everything works, and then I run some tests and get the following error:
In the error log I see:
Rebuilding doesn't help, nor does closing and re-opening Visual Studio. Sometimes, if I click on a single unit test and run that, it works. It somewhat appears that I might get myself into this state if I run an entire session and one of the tests in that session fail. It's tough to really for sure, but mainly I'd like to understand what this error means and what "left pending" implies.
I'm running Visual Studio Pro 2017 (Version 15.5.6)
reSharper Ultimate 2017.3.2
MSTest.TestAdapter NuGet Package 1.1.18
MSTest.TestFramework NuGet Package 1.1.18
Any ideas would be helpful!