1. Sumproduct is not an array function. Use Enter, not Ctrl-Shift-Enter.
2. You must convert false/trues to numbers. One way:
=SUMPRODUCT(($B$1816:$B$2400=$A2402)*(C$1816:C$240 0<0)*(C$1816:C$2400))

Regards,
Fred

"Eric" wrote in message
...
I would like to sum all numbers, which match following conditions,

=SUMPRODUCT(($B$1816:$B$2400=$A2402),(C$1816:C$240 0<0),(C$1816:C$2400))
press ctrl + shift + enter

but it returns zero, and I have checked it, zero should not be the result.
Does anyone have any suggestions what wrong with sumproduct function?
Thanks in advance for any suggestions
Eric