=SUMPRODUCT(--([RNP_SAFETY_ONHAND.xls]Sheet1!$A$2:$A$10000=$C8),--([RNP_SAFETY_ONHAND.xls]Sheet1!$B$2:$B$10000=$D8),--([RNP_SAFETY_ONHAND.xls]Sheet1!$C$2:$C$10000=$E8),([RNP_SAFETY_ONHAND.xls]Sheet1!$D$2:$D$10000))

Here is the almost identical formula just a few cells to the right hand side that doesn't work properly. The only difference is that the fourth array is in column E instead of Column D.

=SUMPRODUCT(--([RNP_SAFETY_ONHAND.xls]Sheet1!$A$2:$A$10000=$C8),--([RNP_SAFETY_ONHAND.xls]Sheet1!$B$2:$B$10000=$D8),--([RNP_SAFETY_ONHAND.xls]Sheet1!$C$2:$C$10000=$E8),([RNP_SAFETY_ONHAND.xls]Sheet1!$E$2:$E$10000))

It returns a zero value even though I know the data would return numbers like 1200 etc easily. I'm completely stumped. I have searched the net over and found no reason why this wouldn't work.

I'll need this formula to work in versions as old as 2003 and I will have many cells like it as this formula carries down as many as 400 rows at a shot in other worksheets. I'm trying to use the SumProduct command because it will work without having to actively update or open excel files. It is supposed to just work. Is the number of formulas or criteria causing the problem?