Conditional Formatting To Red out a Row, if ID# has been used before
I am trying to create a conditional formatting to mark a row Red if the ID# has been used before. I have plenty of conditional formatting experience however I just can't seem to figure this part out. Basically in a list of projects I.e 1,2,3,4,5 they move at different speeds and sometimes a project wont be on a newer sheet so numbering can get confusing. If a 2nd project were to be added as project 4, I would want both to go red so I know to update 1 of them.
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