Microsoft 365 Alert – Service Degradation – Exchange Online – Some users may be unable to access shared mailboxes from Outlook on the web – RESOLVED

Announcements Sourav Nandi

16/04/2024 09:05:00 AM

NHSmail Reference: INC42483619/ INC42471185

Microsoft Reference: EX777095

Issue Status: RESOLVED

Issue Description: Some users may be unable to access shared mailboxes from Outlook on the web.

More Info: Users can access their shared mailboxes from the Outlook desktop client and Outlook mobile to avoid this issue. Additionally, if users are actively reproducing the issue on Outlook on the web, as a potential workaround we recommend users sign out of the session to ensure the existing cookies are cleared, then access Outlook on the web using the direct link for the shared mailbox, and sign in again.

Final Update: 19/04/2024 08:39:00 AM – The fix completed deployment and Microsoft confirmed with affected users that impact is remediated.

Scope of impact: Some users attempting to access shared mailboxes from Outlook on the web may be impacted..

Root cause: A recent Outlook on the web build within our service infrastructure is causing some requests to access shared mailboxes to fail unexpectedly.

Next steps: Microsoft are reviewing their Outlook on the web build validation procedure to determine methods of improving the identification of similar issues in service builds that are deployed in the future.