I've been running BizTalk 2009 on my Windows 7 machine, and after installing VS 2010 beta 2, the Enterprise Single Sign-On Service stopped working.
It failed with the following error:
Could not create SSOSQL. To fix the problem, reinstall SSO or try 'regasm SSOSQL.dll' from a Visual Studio command prompt.
Error Code: 0x80131700
The file is located at C:\Program Files\Common Files\Enterprise Single Sign-On\SSOSQL.dll
Run Visual Studio Commmand prompt as Administrator and run 'regasm "C:\Program Files\Common Files\Enterprise Single Sign-On\SSOSQL.dll"'.
On 64 bit machines (windows 7, Vista, W2008 etc) you need to call regasm.exe utility explicitly from this folder: