Nadya
After I responded, I noted that aborant behavior was sporadic, but both cbo's behave alike. The only commonality between the 2 controls is the controlSource table: apInvPoItems. Hence, apInvPoItems had to be the problem. Taking your lead, I selected apInvPoItems in the init event of the data envronment of the called form and issued a "go top". (I had concentrated on go top in the rowSource before this,which didn't work). That was the winner! I have never had to do that before, but I will do it in the future.

Thanks, vince