I am using SUMPRODUCT to count mulitple criteria in different columns. It has
worked up to this point, but I am now getting a VALUE!error and am not sure
why.

Here is the scenario: 2 columns
Month Type
Jan A
Jan B
Feb A
Feb B

I need to count the error types by month. My fomula looks like this:
=SUMPRODUCT(--(Month="Jan"),--(Type="A"))

Month and Type are named ranges. I have also tried replacing the criteria
with cell references.

Thank you.