Microsoft 365 Alert – Service Degradation – Microsoft Teams – Users may be unable to view or use the embedded Microsoft Teams chat panel in Edge, Outlook, or Outlook on the web – RESOLVED

Announcements Arpan Das

30/01/2026 08:50:00 AM

NHSmail Reference: INC46737632

Microsoft Reference: TM1259600

Issue Status: RESOLVED

Issue Description: Users may be unable to view or use the embedded Microsoft Teams chat panel in Edge, Outlook, or Outlook on the web.

More info: When users attempted to open the Microsoft Teams chat panel in Edge, Outlook, or Outlook on the web they may have received an error that stated the chat couldn’t be loaded or a blank chat list.

Final Update: 24/03/2026 08:47:00 AM–Microsoft has reversed the offending service update and confirmed through service health telemetry that the impact has been remediated.

Scope of impact: Any user attempting to view or use the embedded Microsoft Teams chat panel in Edge, Outlook, or Outlook on the web may have been impacted.

Root cause: A recent performance optimization service change introduced a code issue that caused impact.

Next Steps: Microsoft are reviewing their service update testing and validation procedures to identify and prevent similar code issues affecting the Microsoft Teams chat panel in deployments moving forward.