Visual studio 2008 wont debug unit tests anymore. It used to work fine

I have a project that uses Visual Studio test suite. One day I opened another instance of Visual Studio with a project that was using NUnit. I looked at and ran a few of the Unit Tests in that project and now my Visual Studio Unit tests are no longer working. Everything just passes. I cannot hit a break point or anything. Something has totally whacked my Unit Test project. How can i fix this? The green/yellow icons are there (using resharper) but I am unable to hit break points any more. What the heck happened? Can anyone out there help me to fix this? I tried deleting the test results folder in the solutions based on another post I read 开发者_Go百科but that didn't seem to work. Please help if you have any ideas.

Thanks, ~ck