Yesterday (in the midst of trying to get some builds done to get to a release), the Build node of my Team Explorer window for all Team Projects under my main user account went stupid and was displaying a red X for unavailable. Very frustrated, I did some searching and found very little other than one post suggesting that killing my user account and recreating it from scratch would clear the problem. That would also have cost me hours of reconfiguring other programs and settings that are customized under my account, so I dismissed that.
Based on that though, I went and created a separate user account and was able to run builds from there and switch back and forth with Switch User to get through the day.
The sweet thing was that when I fired up VS 2008 this morning and went to Team Explorer with no project loaded, I noticed a bunch of stuff get spit into my output window. Looking closely, it was a nice little error message from Team System telling me the BuildPackage was not being loaded due to previous errors, and if I wanted to have it try again, just launch VS from the command prompt with the following line:
Worked like a charm and my environment is totally happy again.
You gotta love software that detects its own problems and suggests simple things that actually work to fix it.
Well done VSTS team!