I have the following fields in a spreadsheet:

Order Number
Product A
Product B

I created the following to count the number of orders that had 1 or
more of Product A or 1 or more of Product B in them:

Count of Prod A: (=COUNTIF(D2:D8611, "0")
Count of Prod B: (=COUNTIF(E2:E8611, "0")

Now, what I'd like to do is create a column that will display the
number of orders that have both Product A and Product B.

I've tried this: =(COUNTIF(D2:D8611,"0")+COUNTIF(E2:E8611,"0")) but
that gives me the sum of both fields where there is 1 or more product.
Thanks in advance.