In D2:
=SUMPRODUCT((A2:A10=--"23 Oct 2007")*(C2:C10="X"),B2:B10)

How would that work when his data uses "10" for October?

It'll work fine as long as the dates in col A are real dates (presumed). The
double minus in: --"23 Oct 2007" converts the text string to a real,
specific date, as per OP's specs.
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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