Microsoft 365 Alert – Service Degradation – Microsoft Copilot (Microsoft 365) – Some users may experience errors and disruptions when starting or continuing chats in Microsoft Copilot – RESOLVED

19/01/2026 08:36:00 AM

NHSmail Reference: INC46727325

Microsoft Reference: CP1219289

Issue Status: RESOLVED

Issue Description: Users may experience errors and disruptions when starting or continuing chats in Microsoft Copilot.

More info: Affected users receive error messages such as: “A problem has occurred”, “Something went wrong,” or that the service is unavailable.

Some users were also unable to publish agents created in Microsoft Copilot within Microsoft Teams.

Final Update: 19/01/2026 15:40:00 PM – Microsoft has determined that a recent standard service update inadvertently contains a code regression, which is resulting in impact. They are reverting the offending change to remediate impact.

Scope of impact: Impact was specific to some users attempting to utilize chats in Microsoft Copilot, or publish agents created in Microsoft Copilot within Microsoft Teams.

Root cause: A recent standard service update inadvertently contained a code regression, which was resulting in impact.

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