Microsoft 365 Alert – Service Degradation – Exchange Online – Some delegate users” unprocessed meetings may not show as tentative on their calendar in Exchange Online – RESOLVED

20/01/2023 09:10:00 AM (GMT)

NHSmail Reference : INC33749550

Microsoft Reference : EX496574

Issue Status : RESOLVED

Issue Description : Some delegate users” unprocessed meetings may not show as tentative on their calendar in Exchange Online.

More Information :Affected users may also see general delegate calendar sync issues where updates and edits made for meetings may not be reflected on delegate calendars for up to three hours, after which an automatic sync applies the changes. This issue may occur through any connection method for affected delegate users. From the principal user”s calendar view, the new meeting displays correctly as tentative. When some delegates view affected meeting requests, the calendar view from the invite displays the following error: “We couldn”t find this meeting in the calendar. It may have been moved or deleted.” If the delegate processes the invite (Accept/Tentative), they then see the calendar item show in their copy of the principal”s calendar.

While the fix is continuing to saturate throughout the affected environments, please try turning off shared calendar improvements for affected users in the Outlook desktop client to bypass the issue. Once the fix is fully saturated, please turn shared calendar improvements back on for those users to avoid performance issues. Instructions can be found here: https://support.microsoft.com/en-us/office/how-to-enable-and-disable-the-outlook-calendar-sharing-updates-c3aec5d3-55ce-4cea-84b0-80aab6d8dc26

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Current Update : 17/02/2023 13:10:00 PM – Microsoft have confirmed that the fix has saturated to 99.9 percent of the affected infrastructure and that impact should now be remediated. They are awaiting confirmation that the issue is resolved from a sample of affected users.

Scope of impact : Impact may occur for some delegate users attempting to view unprocessed meetings received by the principal user or apply delegate calendar updates and edits made for meetings.

Root Cause : A recent service update that was intended to optimize service functionality introduced a code regression and is inadvertently causing impact.

Next Steps : Microsoft are reviewing the update procedures to better identify similar issues during the development and testing cycles.