I'm using Visual Studio 2008 Team Suite and i was able to run tests until a couple of weeks ago. I run VS as myself in Vista as my user account which is non-admin and UAC enabled. I get "Exception has been thrown by the target of an invocation." OK message box when clicking run test in team suite mstest. If I open the exact same solution in VS running as administrator the test will run. I watched process access in procmon and noticed that as non-admin the MSTestHost.exe process is never even started, so it doesn't get that far. I'm limp along running VS as admin, but I would really like to get back to my old dev environment. Can anyone help? -- Jay R. Wren