Microsoft 365 Alert – Service Degradation – Exchange Online – Some users may see add-ins in Outlook desktop and Outlook on the web that aren’t installed or removable – RESOLVED

Announcements Arpan Das

13/03/2025 09:06:00 AM

NHSmail Reference: INC46474938

Microsoft Reference: EX1027699

Issue Status: RESOLVED

Issue Description: Users may see add-ins in Outlook desktop and Outlook on the web that aren’t installed or removable.

More info: As a temporary workaround, affected users can disable ‘Show Apps in Outlook’ for relief, but this only applies to classic Outlook on Windows. There is no workaround for Outlook on the web, new Outlook on Windows, or Outlook for Mac.

Final Update: 14/03/2025 04:10:00 AM– Following the deployment of Microsoft’s fix, their internal tests and validations from affected users have confirmed that the code problems have been addressed, and that impact has been remediated.

Scope of impact: Some users may see add-ins in the Outlook desktop client and Outlook on the web which aren’t installed and can’t be removed.

Root Cause: A service update to a portion of service infrastructure that facilitates identification of which add-ins are enabled for users in Outlook on the web and the Outlook desktop client contains a code issue, resulting in impact.

Next steps: Microsoft are further analyzing the offending service update so they can help identify similar issues during their pre-deployment testing and validation processes.