Use Excel data validation to prevent duplicate values in a column Your email has been sent Prevent duplicates before they happen by combining a simple function with data validation. Excel has built-in ...

When you're working with a spreadsheet, duplicate data can sometimes make its way in and cause all sorts of problems. In this how-to, we demonstrate two methods of using Microsoft Excel for ...

Duplicates in the same column are easy to find by sorting or filtering. Duplicates that span multiple columns require a bit of setup, but the solution's not difficult to implement. Finding duplicate ...