So as part of my experiments with creating and installing Work Item Custom Controls for use in Team Explorer 2010 I inevitably wanted to be able to attach a debugger to an instance of Team Explorer 2010 to interrogate the Work Item object model at runtime.
I’ve done this before for Team Explorer 2008 and wasn’t anticipating any problems. The basic setup can be obtained using these instructions on the Team System Notes blog.
Having followed these instructions I hit a bit of a roadblock. It turns out that VS2008 doesn’t like attaching a debugger to a VS2010 instance. If VS2010 is setup as the start-up application then an error is thrown when starting the project: “The debugger’s protocol is incompatible with the debuggee“. I’m guessing here, but I’d assume that the issue is that VS2010 has been compiled using .NET 4.0, and as VS2008 only supports up to .NET 3.5 the debugger is unable to correctly attach to a 4.0 managed process. I had hoped to keep this machine (the primary one I use for work) free of the full VS2010 components … however having hit this issue I’ve had to download and install the beta 2.
Anyway, the upshot is that installing VS2010 and attaching the debugger to another VS instance from there solved the problem.