add this to your formula
1-ISBLANK(C1:C6)

=SUMPRODUCT(1-ISBLANK(C1:C6),--(pathfinder_dump!G1:G10000=TIME(1,0,0)),--(pathfinder_dump!G1:G10000<=TIME(1,29,59)),--(pathfinder_dump!I1:I10000=0))

"JR" wrote:

Hello,

I am using the following to count a column of zeros in a worksheet if the
zeros occur during specific times.

=SUMPRODUCT(--(pathfinder_dump!G1:G10000=TIME(1,0,0)),--(pathfinder_dump!G1:G10000<=TIME(1,29,59)),--(pathfinder_dump!I1:I10000=0))

The trouble is that the formula is counting the blank cells as well. Can
someone tell me how to modify so the formula only counts the zeros?

Thanks