Thanks much to both of you. This was a good lesson in aliasing for me and I plan on doing some more reading and practice.

sorry bp, i still get the error message

Server: Msg 207, Level 16, State 3, Line 1

Invalid column name 'y.UserID'.

Thanks Gary - for your code I get:

Server: Msg 107, Level 16, State 2, Line 1

The column prefix 'T' does not match with a table name or alias name...

Thanks for the quick response. I get the error message in QA:

Server: Msg 209, Level 16, State 1, Line 1

Ambiguous column name 'UserID'.

Server: Msg 209, Level 16, State 1,...

I can ping the server, the open port is 1520 which I've specified in the connection string. Is there any other place I have to specify the open port?