I am trying to get a formula that
1. if a cell in column c is greater than zero will multiply that cell by
another and total the result by column.

What I have is (which is not working)

=SUMPRODUCT(--($C$7:$C$640),$C$7:$C$64*D$7:D$64)


Column C Column D
5 100
0 400
2 300
4 200

= 500+600+800


Thanks,


Todd