Dominique,

Try
=SUMPRODUCT(--(diary!I1:I1000="510"),--(diary!C1:C1000="6"))
SUMPRODUCT cannot work on complete columns.

also, take a look at http://www.xldynamic.com/source/xld.SUMPRODUCT.html to
get a better understanding of the function.

--

HTH

RP
(remove nothere from the email address if mailing direct)


"Dominique Feteau" wrote in message
...
I always have trouble setting up sumproduct functions.

I have a sheet called "diary". In column I, i have diary codes (505, 510,
ect.). In column C, i have number codes that break down each diary code
(1-8). I want to count how many of each number code, i have for each
diary
code. I'm using this function, but it returns an error. What am i doing
wrong?

=SUMPRODUCT((diary!I:I="510")+(diary!C:C="6"))