I seem to have inherited a nasty little bug in the last day or so with Visual Studio 2008 (VS2008) and Team Explorer. Up until yesterday morning I had been working away quite happily connecting to either our internal TFS server or to our TFSNow TFS server and using VS 2008 to work on projects in them. But yesterday morning when I loaded up VS2008 I noticed that my working TFS server wasn't already connected up... hrmm. Oh well, I imagine that these things happen from time to time, so I manually connected to our TFS Now instance again and voila, I was connected as usual. However when I attempted to load up a solution from Source Control Explorer I was informed that it was not currently configured for integrated source control:
I checked my Source Control settings in Tools | Options and sure enough I had TFS selected as the default source control provider.
Attempting to manually bind the projects didn't work either because there was no recognized server to bind to:

I thought that maybe restarting VS2008 might make the magical difference... but it didn't. In fact, when I restarted VS, it seemed to have forgotten all about my saved server settings again and so I had to repeat the process of re-connecting to the TFS Server.
I tried lots of things after that, I tried:
- Blowing away my workspace and creating a new one - nope!
- Deleting my local TFS cache - nope!
- Reinstalling TFC - nope!
- Reinstalling VS2008 and TFS - nope!
Finally, as a sanity check, I called Mitch to see whether he could connect to the TFS instance and open these projects and he could.
So I'm not really sure. I think that I'll go down the rebuild path. Darn!