Visual Studio 2010 problem with Vault

Working with Visual Studio 2010 and SQL 2008 I got this message out of the blue:
‘System.__ComObject’ to interface type ‘Microsoft.VisualStudio.OLE.Interop.IServiceProvider’. This operation failed because the QueryInterface call on the COM component for the interface with IID ‘{6D5140C1-7436-11CE-8034-00AA006009FA}’ failed due to the following error: No such interface supported (Exception from HRESULT: 0x80004002 (E_NOINTERFACE)).

Whoah… After a reboot, some thought, a few more attempts to build, and a bit of luck, I deduced with reasonable certainty that Vault, which I use for version control, was the culprit.
So I closed Studio 2010 and removed Vault. Then I opened the same solution and did a build with no problems. Next step is to figure out what to do about getting Vault back into play. Or not.