"Success: Test not run" in Test Sessions window (Resharper) in Visual Studio

I use Resharper in Visual Studio 2015 for running tests. However I'm confused with the statuses Test not run - they are there for both Success and Failed. If I run one of such tests separately, the status temporary changes to Pending: Test not run and then back to Success: Test not run. I can't find any info why the test hasn't run. Furthermore I don't understand why the status is Success (or Failed) if the test was not run - how could it know?

How should I interpret the statuses and what can I do to make it run all tests?

(Using VS 2015 Enterprise with Update 1, Resharper Ultimate 10.0.2, both up-to-date to the moment)