Microsoft 365 Alert – Service Degradation – Microsoft 365 suite – Some users may encounter delays triggering automation rules in Microsoft Sentinel – RESOLVED

Announcements Shagufta Naaz

14/01/2026 12:10:00 PM

NHSmail Reference: INC46723928

Microsoft Reference: DZ1217781

Issue Status: RESOLVED

Issue Description: Some users may encounter delays triggering automation rules in Microsoft Sentinel.

More info: This issue occurs across multiple browsers and also when using a private browsing mode. This issue also impacts accessing a Class Notebook using the “Manage” option in the OneNote desktop app.

Final Update: 15/01/2026 08:53:00 AM – Following Microsoft’s application of a manual performance optimization to the impacted service infrastructure, their internal telemetry has verified that impact has been remediated.

Scope of impact: Your organisation is affected by this event, and some users attempting to trigger automation rules in Microsoft Sentinel may be impacted.

Root cause: An unexpected increase in requests caused a section of infrastructure, responsible for triggering automation rules in Microsoft Sentinel, to perform below their manageable service performance thresholds, resulting in impact.

Next Steps: Microsoft are further analyzing the affected subset of service infrastructure to help us prevent similar problems to infrastructure when large amounts of service requests are received.