Microsoft 365 Alert – Service Degradation – Exchange Online – Users may see that after selecting a meeting room when scheduling meetings, it changes from available to unavailable – NEW

19/03/2026 09:25:00 AM

NHSmail Reference: INC46777325

Microsoft Reference: EX1233142

Issue Status: NEW

Issue Description: Users may see that after selecting a meeting room when scheduling meetings, it changes from available to unavailable.

More info: While we are working to remediate the impact, admins can mitigate the issue by assigning the desired working hours and the time zone for the meeting rooms.

Current Update: 19/03/2026 09:20:00 AM –Based on feedback received regarding this communication, Microsoft has edited the More info, Scope of impact, and Root cause sections of this communication to align with their current understanding of the affected scenario. Additionally, they have completed validation of the fix and have begun its deployment. They are monitoring as it progresses and will provide a completion timeline when one becomes available.

Scope of impact: Any users that are trying to select a meeting room when scheduling meetings outside the room’s working hours in Exchange Online may be impacted. This information may be updated as our investigation continues.

Root cause: A recent expansion of the feature logic used to book rooms for scheduled meetings contains a code complication which automatically sets the meeting rooms’ default working hours to appear in Pacific Standard Time instead of their accurate time zone.

Next update by: Friday, March 27, 2026, at 3:00 AM UTC