User impact: Users may see unwanted add-ins appearing automatically across all Outlook clients.

More info: These add-ins are configured to be available to users by admins but aren’t expected to be automatically installed. To bypass this issue, admins can run the “Set-App -Identity -OrganizationApp -PrivateCatalog -DefaultStateForUser Disabled” command to remove add-ins that are unintentionally appearing.

Current status: Our deployment is progressing across affected environments, and we anticipate some users to start seeing remediation at this time. We anticipate impact to be fully resolved by Monday, October 5, 2026.

Scope of impact: Impact may occur for some users that are viewing their add-ins across all Outlook clients. This section may be updated as the investigation progresses.

Start time: Friday, July 17, 2026, at 10:26 AM UTC

Estimated time to resolve: We anticipate impact to be resolved by Monday, October 5, 2026.

Root cause: A portion of the Exchange Online add-in sync pipeline isn’t processing add-in state information as expected. This is causing incorrect EnabledStatus values being returned and Outlook automatically displaying add-ins configured as Available, which is resulting in impact.

Next update by: Monday, September 28, 2026, at 7:00 PM UTC