i do believe it is because i am trying to evaluate from 2 sheets.

Yep!

I think your best option is to break it out into 2 formulas, 1 for each
sheet, then sum both results.

Try these normally entered:

=SUMPRODUCT(--(Sheet1!$A$2:$A$19=A2)--(Sheet1!$B$2:$B$19=B2),--(Sheet1!$C$2:$C$19=13),Sheet1!$K$19)

=SUMPRODUCT(--(Sheet2!$A$2:$A$19=A2)--(Sheet2!$B$2:$B$19=B2),--(Sheet2!$C$2:$C$19=13),Sheet2!$K$19)


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Biff
Microsoft Excel MVP


"Zab" wrote in message
...
hello all,

=SUM(IF(Sheet1:Sheet2!$A$2:$A$19=A2,IF(Sheet1:Shee t2!$B$2:$B$19=B2,IF(Sheet1:Sheet2!$C$2:$C$19=13,Sh eet1:Sheet2!$K$2:$K$19,0),0),0))
ctrl+shift+enter

i was wondering if anyone could help me out with my #ref. i do believe it
is
because i am trying to evaluate from 2 sheets. i can get it to work from
1sheet. can anyone give any assistance?
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Thank You in advance, Brian