Hi Nigel,

This time it does work if the blank-yellow field is between (or contains) A1:DD1. Unfortunately, it doesn't seem any other rows, though. I'm looking at the possibility of clients filling out up to 1000 rows with information that will need to be validated.

I really appreciate you having taken the time to help me out. Not sure if there is a simple way to have the code check all rows?

Thanks!