Professor Excel
How to Prevent Add-Ins to Disappear in Excel.

Excel Add-In Disappeared? 4 Methods to Prevent an Add-In to Disappear

You are using an Excel add-in that keeps disappearing? Also our add-ins, for example Professor Excel Tools, sometimes might disappear after restarting Excel. This article introduces four methods of how to prevent Excel (and other Microsoft Office) add-ins from disappearing.