How to find a duplicate input

Sometimes I have to audit parts that might have the same number. What I need is a way to “see” if I have already inputted a value. I scanned a bar code value into column A. As I scan the next value I need to check if that value has already been entered and if so (conditionally) turn red. Is there an easy way to do this?

Thanks ahead for any suggestions in doing this.

dave

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Of course you can do it with Conditional Formatting

Very good solution, I voted it.

John, Thank you for the answer. This is just what I am looking for. You just made my job easier.

I don’t see how I can vote for this? Sorry John -

You can vote it with :heavy_check_mark: on the left of answer area.

When I re-open, I have to do the condition all over. Is there a way to “keep it”, so it will always work when it is being used?

Charlie, thanks

Perhaps the Office update to the latest version will remove the problem?