Hello,
Please Close Outlook and restart it using Run as Administrator then remove the add-in. Close Outlook and restart Outlook normally when finished.
To Run as Administrator, right-click on outlook.exe or the Outlook shortcut and choose Run as Administrator.If Run as Administrator is not listed, hold Ctrl+Shift+Alt as you right-click on the shortcut to show the full menu.
Regards,
Rajeev.
