Microsoft 365 Alert – Service Degradation – Exchange Online – Users may be unable to view free/busy status for Gmail users within the Exchange Online calendar – ONGOING

Announcements Shagufta Naaz

22/05/2026 08:31:00 AM

NHSmail Reference: INC46832712

Microsoft Reference: EX1310533

Issue Status: ONGOING

Issue Description: Users may be unable to view free/busy status for Gmail users within the Exchange Online calendar.

More info: Affected users may see an “Unknown” status for the external Gmail contacts.

Current Update: 10/06/2026 09:41:00 AM – Following Microsoft successful internal testing and validations they have deployed our solution. The deployment is approximately 81 percent complete, and user impact is expected to be addressed as it progresses. Their fix deployment timeline estimates it will have completed and that the impact will be remediated by their next scheduled communication update.

Scope of impact: Impact is specific to any user attempting to view free/busy status for Gmail contacts in their Exchange Online calendars.

Root cause: Basic Authentication credentials aren’t being correctly forwarded to the third-party service, resulting in the failures to obtain free/busy status responses and causing impact.

Next update by: Friday, June 12, 2026, at 8:30 PM UTC