I had the same problem with 2 of our systems after the upgrade to 2.0.0p3.
Reading the error message i figured there might be a problem with the msoledbsql driver.
So i went ahead and (re)installed it on both servers.
One of them is working fine now, the second one does not.
Since the second server has an SQL Server 2005 installation and is a read-only system nowadays i decided to remove the SQL checks completely.