Failed to load Continuous Testing state.

I have been using Continuous Testing in all my solutions for the past year.  My unit tests are written using Microsoft.VisualStudio.QualityTools.UnitTestFramework and I am using Visual Studio 2015 Update 3.  

Every once in a while when opening a solution the Continuous Testing icon in the lower right would display an error "Failed to load Continuous Testing state." and the continuous testing would not function until I restarted Visual Studio and opened the solution again.  My Resharper Ultimate subscription recently ended and I had to downgrade to version 10.0.2 due to my fallback license.  Now the "Failed to load Continuous Testing state." error appears every time and does not go away by restarting Visual Studio.  

Is there any additional information about the error and/or what I can do to prevent it from happening?  Thank you.