Try:
intRecCount = DSum("ynDelete", "tblCDMRvalues", "[ynDelete] = Yes"

AFAIK, all of the Domain functions take strings as arguments.

In Access, Yes/No values return a -1 if YES and 0 if NO. All you need to do
is multiply your result by -1 and you're fine.

Richard Rost
richard.rost@amicron.com
www.599cd.com
www.AccessLearningZone.com

You are summing values in the ynDelete field.  If that is a Yes/No field, a
Yes value is represented by -1.  You are adding all of these values (sort
of).
The reason I say "sort of" is because your syntax is incorrect.  As ruralguy
pointed out, the criteria part of the expression needs to be a string, but
he left out a closing parentheses.  Try this:
intRecCount = DSum("ynDelete", "tblCDMRvalues", "[ynDelete] = Yes")

If there are three records in which ynDelete is True, the expression will
return -3.  If you wrap it in the Abs function you will get 3 as the result:
intRecCount = Abs(DSum("ynDelete", "tblCDMRvalues", "[ynDelete] = Yes"))

However, since it seems you want to count the records, DCount would be a
more efficient way to go about it:
intRecCount = DCount("*", "tblCDMRvalues", "[ynDelete] = Yes")