Steve,

Just took a new blank form, added an invoice detail table to DE, dropped the table on the form. Added 1 to the grid's column count. Set the added column's ControlSource to invdet.quantity*invdet.sellprice and ran the form. Calculates and displays fine.

>Hmmm. I'm looking at a working form I have here, and nothing strikes me as unusual to get it working. Let me dig a little deeper to see if I buried a 'fix' somewhere...
>
>>Nothing happens in either case.