Has this ever happened to you?
You’re in Designer, minding your own business, trying to build a universe on top of SQL Server 2005 data, and you have no database tables in the table browser. The connection works fine when you test it, you’ve double-checked the ODBC DSN, and everything seems normal. I see this fairly often – especially when using VMs, where the software is infrequently maintained. (That’s a little hint as to the cause of this problem.)
Check that the instance of SQL Server 2005 hosting your default database is up to date on its service packs. You just need to be up to date through SP2 to resolve this. Proof that it works:
Here is a screenshot from the About panel of the updated SQL Server instance with version information: