Problem In Connecting 2 Databases With Sql Server 2005 Express

I am programming in VB6 using ADO 2.8. This connection and query works in MS access, SQL server 2000 and Sql Server 2005. does not work in Sql server 2005 express. Any Suggestions?

Connection String #1 Provider=SQLNCLI.1;Integrated Security=SSPI;Persist Security Info=False;AttachDBFileName=C:Program FilesMaterial_Management_SystemDATAMain.mdf;Data Source=Steve_Laptopsqlexpress

Connection String #2 Provider=SQLNCLI.1;Integrated Security=SSPI;Persist Security Info=False;AttachDBFileName=C:Program FilesMaterial_Management_SystemDATAItems.mdf;Data Source=Steve_Laptopsqlexpress


Sql Query: Select POLINE.ID as POLine_ID, PFMS.ID as Items_ID FROM POLINE LEFT JOIN Items.PFMS as PFMS ON POLINE.lItem_ID = PFMS.ID

Error: Msg 208, Level 16, State 1, Line 1
Invalid object name 'Items.PFMS'

Sql Query#2: Select POLINE.ID as POLine_ID, PFMS.ID as Items_ID FROM POLINE LEFT JOIN Items.dbo.PFMS as PFMS ON POLINE.lItem_ID = PFMS.ID

Error: Msg 208, Level 16, State 1, Line 1
Invalid object name 'Items.dbo.PFMS'.

I am running the queries directly from the 2005 Mgt window to take as many variables out of the equasion. I get the same error in Visual basic

How am I supposed to reference a join of 2 databases? Any suggestions