Does Visual Studio 2010 breaks BizTalk?
This suggests it may have, and I’ve had the same experience – after installing VS2010 my SSO service failed to start with the error -Windows could not start the Enterprise Single Sign-On Service service on Local Computer.
Error 0x80131700: 0x80131700
Interestingly – repairing BizTalk did not solve it, neither did reinstalling it – when trying to configure the SSO service, after a fresh installation, I got the error
Failed to connect to the SQL database 'SSODB' on SQL Server '…'
> > > 0x80131700