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Hello,

This may be a simple question, but I only know the basics of Excel.

I have been given the assignment of creating a spreadsheet that needs to "flag" or give me some sort of prompt when the same name is being added.
For example I have 300 user names on a spreadsheet and if I were to type a name that is already on the list< I would like for Excel to prompt me or flag that name and notify that the name is already in the list. Is this possible?
If so could someone please step me thru this process.

Thanks Alot