I am a big fan of Jamie Cansdale's TestDriven.net. Today I tried to use it in VS2003 and clicking on the Run Test(s) item did nothing! I almost panicked. I couldn't envision going back to nUnit GUI. I checked all the usual suspects. Uninstalled, got the latest build of TestDriven.net, reinstalled, reset the packages in VS.NET, read the FAQ on the TestDriven.net site.
Finally I gave up and sent Jamie some mail. Jamie doesn't know me from Adam. Not only did he respond but he responded within 5 minutes! Had me use SysInternals excellent DebugView to give him a log of what was going on. Looked like there was an issue using EnvDTE to get the active window in VS2003. He pointed me at a Craig Skibo article documenting a problem with some uninstalls unregistering components used by Visual Studio AddIns. Specifically DTE.OLB.
Ran:
regsvr32 "C:\Program Files\Common Files\Microsoft Shared\MSEnv\DTE.OLB"
and I was back in business.
Jamie thanks for a great tool and and spectacular support!