When I use this, I get an error #VALUE

That usually means you have #VALUE! error value(s) within your data, either
in col B and/or col D, or col D might contain some cells with text (instead
of real dates/numbers). Check it and clear these cells.

Above said, perhaps a more unambiguous/robust summation to try, as hinted in
JMB's question to you would be something like this:
=SUMPRODUCT(--(B1:B250="Option A"), --(TEXT(D1:D250,"mmmyyyy")="Aug2007"))
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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