On Thursday afternoon, Microsoft 365 experienced a widespread outage that disabled Outlook, Teams, Microsoft Defender, Purview, and the Microsoft Store for millions of users across North America. The disruption began around 2:30 p.m. ET, caused intermittent connectivity, and prompted Microsoft to confirm the issue and work on restoration. The incident also impacted performance of related services and triggered extensive monitoring by Microsoft’s engineering teams.
What Happened During the Outage
The outage affected both web and desktop clients of Outlook, the Teams collaboration platform, Microsoft Defender security tools, the data‑governance solution Purview, and the Microsoft Store. Users reported login failures, error messages, and loss of functionality across these services.
Timeline of the Incident
- 2:30 p.m. ET (Thursday): Outage reports surge for Outlook, Teams, Defender, Purview, and the Microsoft Store.
- ~3:00 p.m. ET: Users share screenshots of error messages, increasing visibility of the problem.
- 3:30 p.m. ET: Thousands of complaints logged, marking one of the most reported Microsoft 365 disruptions in recent months.
- Later that afternoon: Microsoft acknowledges the outage on its service health dashboard and begins remediation efforts.
Background on Microsoft 365 Reliability
Microsoft 365 is a cloud‑based subscription suite that combines Office applications, email, collaboration tools, and security services. While generally reliable, large‑scale outages can occur due to data‑center failures, network routing issues, or problematic software updates. This incident appears limited to specific geographic zones in North America.
Impact on Users and Businesses
Outlook downtime delayed email delivery, missed meeting invitations, and blocked calendar access. Teams users experienced dropped calls, frozen chats, and inability to join meetings, disrupting remote collaboration. Microsoft Defender showed reduced telemetry and delayed alerts, potentially affecting threat detection. Purview’s dashboards were inaccessible, hindering compliance monitoring. The Microsoft Store suffered download failures and slow page loads, affecting both developers and consumers.
Microsoft’s Response and Recommended Actions
Microsoft publicly confirmed the outage and provided ongoing updates via its service health portal, stating that engineers were actively working to restore full functionality. Organizations are advised to maintain secondary communication channels, such as alternative email providers or instant‑messaging platforms, and to regularly test disaster‑recovery procedures to mitigate future disruptions.
Looking Ahead
Microsoft typically releases a post‑mortem analysis after major incidents, detailing root causes and preventive measures. Stakeholders should monitor for this report to understand any long‑term architectural or operational changes aimed at reducing the likelihood of similar outages.
