Excel: if duplicate cell value found in another column then highlight green

Question

Can someone help me, I'm not sure what formula to use.

I have highlighted the cell in the picture to show an example of what I mean.

What I want to do is highlight the cell in column A where the value matches a value in column D, it does not have to be in the same row. If there is a duplicate value in column D then highlight the cell in column A green. Thanks for any help given.

Solution

Try this as the conditional format formula

=MATCH(A1,$D:$D,0)