Rowsource for combo box doesn't work anymore

I'm working with ADO for this Access Data Project (ADP), I have a combo box

that fills up with supervisors related to cost centers selected in another

table.

I used to just fill the rowsource with an SQL String on the GOT FOCUS
event.
This used to work fine.

I decided to use Transactions with ADO and now when I'm in the middle of a

transaction I get a timeout error on the Got Focus event....

What should I do to make the rowsource work again?

Here is the SQL String


Dim strSQL As String

    'strSQL = "SELECT * from vwSups cmbSups " _
        & "WHERE exists (Select * " _
        & "FROM tbl_Delegatee_CC as DelCC " _
        & "WHERE cmbSups.[Cost Center] = DelCC.FullCCNum and Del_ID = " & 
lDelID & ") and not exists (select * " _
        & "FROM tbl_DelSup DelSups " _
        & "WHERE Supervisor = cmbSups.Supervisor and DelID = " & lDelID &
")"