Microsoft 365 Alert – Service Degradation – Microsoft Defender XDR – Admins’ allow and block policies for apps may not be honored, affecting users’ app access based on those policies – RESOLVED

Announcements Arpan Das

12/02/2026 08:43:00 AM

NHSmail Reference: INC46749377

Microsoft Reference: DZ1231199

Issue Status: RESOLVED

Issue Description: Admins’ allow and block policies for apps may not be honored, affecting users’ app access based on those policies

More info: The affected users’ policies that block or allowed app availability aren’t being honored. Users can determine which apps are impacted based on their policies.

Final Update: 16/02/2026 08:25:00 AM – Microsoft has completed the deployment and confirmed that Cloud discovered app blocking is re-enabled across all regions.

At this time, administrator configured block policies may still not be fully honored, which could allow users to access some apps that are intended to be blocked by your organization. They are currently conducting validation testing before proceeding with the full remediation actions.

Scope of impact: Any user with policies that allow or block apps may be impacted.

Next Steps: Microsoft are continuing to monitoring for service reliability while refining deployment and validation processes to reduce the likelihood of similar issues in future releases.