Annoying Debug problem with VS2005

Earlier today I was running the Debug build of a program (though outside of the debugger) when it crashed and required me to open Task Manager to end it (this is with Windows 7 BTW). Ever since this happened, the Debug build of that particular app is running incredibly slowly. Actions that are normally imperceptibly quick (screen redraws etc) are taking 20 seconds or more. It makes no difference if I run the app inside the debugger or outside.

First thing I tried was powering down and rebooting but that didn't make any difference. Next I tried rebuilding the Debug version but that didn't help either. The Release version still builds fine and runs normally but the Debug build is ludicrously slow. It almost looks as if I'm single stepping through the code!!! No other apps seem to be affected - only the one that crashed.

I quickly realised it wasn't a cpu hogging problem (cpu usage is around 1% - 2%, as usual) so I figured it might be a problem with a program database file - so I deleted all its pdb files and rebuilt again but that hasn't made any difference either! :cry:

Has anyone ever encountered a problem like this? It's a new one on me so any suggestions would be very welcome....