Fix: The Call to GetCustomUI() for RibbonId “Microsoft.Outlook” – Outlook

You may receive an error every time you look at an item in your Microsoft Outlook calendar or create a calendar event.

Custom UI Runtime Error in Enterprise Connect

The call to GetCustomUI() for RibbonID “Microsoft.Outlook.MeetingRequest.Read” failed.

There are a few things to try to avoid getting this annoying message prompt in Outlook.

1. This error is most likely caused by an Add-In for Microsoft Outlook.

2. In Outlook, go to File -> Options -> Add-Ins -> Manage -> Go

3. Disable Enterprise Connect and Enterprise Connect Task Pane add-ins.