Microsoft 365 Alert – Service Degradation – Microsoft Defender XDR – Some admins may experience delays in Microsoft Defender for Endpoint detections – NEW

27/08/2026 09:20:00 AM

NHS.net Connect Reference: INC46920249

Microsoft Reference: DZ1462187

Issue Status: OPEN

Issue Description: Admins may experience delays in Microsoft Defender for Endpoint detections.

More info: Affected admins may experience delays in receiving Microsoft Defender for Endpoint detections in the Microsoft 365 Defender portal and Microsoft Sentinel.

Current Update: 27/08/2026 09:21:00 AM – Microsoft has implemented performance optimisations to assist with restoring the affected section of the detection processing infrastructure that was causing delays, and they have validated from their service monitors that users are now receiving new Microsoft Defender for Endpoint detections in the Microsoft 365 Defender portal and Microsoft Sentinel. They are processing the backlog of affected Microsoft Defender for Endpoint detections, and they aim to provide a timeline to remediation by their next scheduled update.

Scope of impact: Some admins expecting to receive Microsoft Defender for Endpoint detections in the Microsoft 365 Defender portal and Microsoft Sentinel detections may be impacted. This information may be updated as their investigation continues.

Root cause: A section of the detection processing infrastructure that is causing delays in the detections pipeline.

Next update by: Thursday, August 27, 2026, at 5:00 PM UTC