How to remove duplicates in Microsoft Excel to clean up data in individual or multiple columns

You can remove duplicates in Excel in a few steps. Duplicates can create problems when you're dealing with data.
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Everything You Need to Know About Data Validation in Microsoft Excel

To apply data validation rules to a selected cell or range, head to the "Data" tab on the ribbon, and click the top half of the "Data Validation" icon if you're using a wide screen, or the left half ...