I’m trying to install BizTalk 2006 R2 Developer edition on my machine and encountered this error:

Failed to connect to the SQL database SSODB on SQL Server ‘localhost’. (SSO).

So the first thing I check is whether indeed there’s a valid connection and permission to my local db.

Took me another 10 mins of googling and found this solution:

1. Go to C:\Program Files\Common Files\Enterprise Single Sign-On folder then type in

2. regasm SSOSQL.dll

Tried it again and error is gone..