I have four Excel files that contain email addresses. I need to find out how many unique addresses are in the first three, but not in the fourth.
What's the easiest way to do that?
If you can copy all of the data into one sheet, you can use the 'remove duplicates' (under Data) to find unique addresses. If you colour-code the entries from each file first, you'll be able to tell which came from where, and which ones are left over.
If you used background colours to code the entries, you can use this function to count the entries.
If you coloured the font, you can use this function, taking care to replace 'Interior' with 'Font' as noted in the explanation at the top.