- A Microsoft 365 outage that began November 12, 2026 has disrupted Outlook, Teams, and Copilot across 74 countries and territories.
- Microsoft’s initial fixes, including scaling up virtual machines, failed to deliver lasting improvement, and the company is now evaluating traffic throttling and failover routing.
- Downdetector logged nearly 130,000 Outlook-related reports in the US alone, with users unable to send or receive email or reach workplace apps.
- Microsoft traced the disruption to a core process for establishing secure connections on Exchange Online servers that became overwhelmed and stopped processing requests.
What Happened
A global Microsoft 365 outage that began Thursday, November 12, 2026 has disrupted Outlook, Teams, Copilot, and related apps across 74 countries and territories, and Microsoft’s initial recovery steps have not resolved it. Analytics India Magazine reported on the stalled fix on November 13, 2026.
Why It Matters
The outage lands weeks after Microsoft touted strong Copilot adoption, including 20 million paid M365 Copilot seats and a 20% quarterly usage gain, putting reliability back in focus just as enterprise customers lean more heavily on the suite.
Technical Details
Microsoft said the disruption originated in Exchange Online, the cloud email infrastructure behind Outlook, after a core process responsible for establishing secure server connections became overwhelmed and stopped processing requests. The company first tried scaling up virtual machines to add capacity, but ran into problems synchronizing network changes as some machines remained stuck in an abnormal state. A recent network configuration change correlated with the incident’s start, though Microsoft has not confirmed it as the root cause. Downdetector logged nearly 130,000 Outlook-related reports in the US alone.
Who’s Affected
Teams lost calendar access, meeting scheduling, and some organizational chat features, though core messaging and meetings stayed largely functional; SharePoint file access remained available except where it depended on Exchange Online. Word, Excel, PowerPoint, and OneDrive saw varying degrees of disruption.
What’s Next
Microsoft said it is evaluating additional traffic controls, including throttling and failover routing, and plans to publish a post-incident report detailing the root cause once the issue is resolved. The company said it found no evidence of malicious activity.
