A Microsoft outage on Thursday, Nov. 12, cut off Outlook email, Teams, Copilot and other Microsoft 365 services for users around the world. Microsoft first reported trouble reaching Exchange Online mailboxes in the Americas at 12:54 p.m. ET. Thirteen minutes later, it said users in any region could be hit. At 6:04 p.m. ET, Microsoft said it was seeing "limited recovery." An hour later it said servers it had brought back "can become unresponsive again once they receive traffic." At 8:59 p.m. ET it reported "positive results" restarting servers in isolated parts of its system. Service was not fully back.
What Microsoft says went wrong
Microsoft's account changed as the day went on. At first it said part of its system was under "elevated load" in several regions, and it moved traffic to other servers. At 2:31 p.m. ET it said the load "isn't driven by an increase in traffic, but by a number of servers being unexpectedly unavailable." It said that strained the servers still running.
The servers were failing automatic health checks, Microsoft said. It said the failures "may originate from a specific component that's responsible for processing server health." It paused all deployments, which means rolling out changes, and began restarting the affected servers. At 3:19 p.m. ET it said it had "not identified any recent change correlated with the start of impact." At 4 p.m. ET it said a new health check method let "a subset of affected servers" come back. By 4:40 p.m. ET it was weighing whether undoing "a small number of recent configuration updates" could "help accelerate recovery."
At 5:09 p.m. ET, Microsoft said its steps "have not provided the anticipated relief." It said "a core process on affected servers is becoming overwhelmed, causing capacity loss." It was testing a fix on part of its system before using it more widely. At 6:04 p.m. ET it said some servers were back and "remain stable so far." It said users "may experience a gradual recovery as their clients reconnect." At 7:06 p.m. ET it said those servers could fail again under traffic. It began limiting which kinds of traffic reach them in some places, and rebuilding some servers "using a previous configuration" to test whether that helps. At 8:59 p.m. ET it said it was "seeing positive results" restarting servers in isolated sections, and would expand that "more broadly" once they proved stable.
How big it was
Downdetector, a site that counts user complaints, said Outlook reports peaked at more than 2,000 times their normal level. By 1:25 p.m. ET, reports about five Microsoft services reached 19,650 a minute. On a normal Thursday it is fewer than 15. The Associated Press said more than 120,000 people had reported Outlook problems by about 1:30 p.m. ET. Reports came from 74 countries and territories, and in the first two hours nearly 3 in 10 came from outside the U.S. These are complaints, not a count of everyone affected.
Was it bigger than Microsoft?
The record so far shows no sign of a shared cause. Profoundd checked the status pages of Google Workspace, which runs Gmail, and Amazon Web Services at about 6 p.m. ET. Neither showed a new problem that day. Cloudflare's page listed a minor problem that began at 5:39 p.m. ET, hours after Microsoft's trouble started. During the same hours, Downdetector also flagged Bluesky, Starlink, OpenAI and some Blizzard games. Nothing so far links them to Microsoft. In the alerts Profoundd read, Downdetector raised none for Gmail, AWS, Cloudflare, Zoom, Steam, X or Facebook. Some users did report Google and AWS problems to Downdetector, CNBC said. Amazon said on X that its services were "operating normally" and that an "unrelated disruption elsewhere on the internet is prompting some inaccurate news reports." Even Microsoft's own Xbox, GitHub and LinkedIn saw far smaller rises, Downdetector said.
What Microsoft has not said
As of its 8:59 p.m. ET update, Microsoft had not named a root cause or said how many customers lost service. It had not said when it expects a full fix, or whether business customers will get service credits. A separate Teams problem in North America earlier that day had been fixed, Microsoft said, according to ABC News.
Reporting through Thursday, November 12, 2026, 9:15 p.m. ET. Sources: Microsoft 365 Status, incident updates EX1550543 and MO1550821, Nov. 12, 2026; Downdetector, outage summary and alerts, Nov. 12, 2026; The Associated Press via NBC News, Nov. 12, 2026; ABC News, Nov. 12, 2026; CNBC, Nov. 12, 2026; Google Workspace Status Dashboard; AWS Health Dashboard; Cloudflare System Status.
