A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
Activate the Formulas tab of the ribbon.
In the Formula Auditing group, click the drop-down arrow on the right-hand side of the Error Checking button.
Select Circular References in the drop-down menu.
Click on the cell reference in the fly-out menu. This will take you to the cell, so that you can investigate its formula.