I have the following formula: =SUMPRODUCT(--('Tab 2'!E3:E50='Tab
1'!D1),--('Tab 2'!C3:C50='Tab 1'!A6),Tab 2'!I3:I50)

I need to change the first criteria to equal 'Tab 1!D1 or D2, but I don't
know exactly how to change the formula. The result needs to sum the values
in I3:I50 that also have values in column C that equal A6 and values in
column E that equal D1 or D2.

I hope I made that clear enough.