It looks like there are a lot of people that got this error when going from beta2 -> RC1, but this was on the RTM version. The thing that's tricky is that now the designer is so nice for us, it adds default values to public properties. Well, since the code that was being called was basically a wrapper for mshtml, I guess you could say COM was involved (like a third cousin). In order to find this bug (in my code, but my code generated by VS2005.) I had to fire up another devenv.exe instance and set it to attach to the first devenv's process for debugging. I don't know the exact workaround for this yet...maybe making the particular property that was causing trouble readonly w/ an accompanying SetProperty(value) method that would still let the underlying value be set. See the problem is that VS regenerates all that goodness for me, so whenever a change is made and saved in the designer I would be facing the same problem, have to hunt down one line of code, and start over again. Boo.

Is there a way to turn off the designer's new behavior?