Microsoft outage leaves Outlook, Teams, Copilot disrupted for 11 hours: Here’s what happened

Reports came in from 74 countries and regions within about an hour, and reports of Outlook were at more than double their usual amount of reports.

The company cited "elevated load" on its infrastructure for the outage.However, Teams' basic operations like attending calls, meetings, and chats were not affected.

However, its calendar functionality, live events, contact synchronization, and Copilot responses faced disruptions.According to Microsoft, a modification that was supposed to enhance the service "wasn't behaving as expected." It said that it was now exploring "alternative workstreams" to enhance capacity due to "traffic management imbalances." Earlier, it had said that it was "aggressively pursuing all avenues" and had rebooted servers.Microsoft says the outage was not caused by a cyber-security incident.

A technology expert told the BBC that if that is true, it amounts to "incredible incompetence." No root cause has been published.Microsoft 365 application users are more than 430 million people.

Both OpenAI and Anthropic noted an issue and OpenAI mentioned that connections to Microsoft would not work anymore.

The spokesperson for Deutsche Bahn said that due to email delays it was challenging to distribute the timetable for diversion of train schedules.Japan government's common information technology platform was also affected.

According to the digital minister of Japan Toshiharu Furukawa, government organizations had to communicate using phone, chat, and text messages to continue working.

In China, where access to a lot of western companies' applications is not allowed, Outlook is among the few reliable channels for international communications.In Australia, the Australian Computer Society renewed its call for a review of which critical IT systems depend on a single provider.

Chief executive Dr Prins Ralston said the outage "exposed Australia's reliance on foreign technology," particularly for small businesses.The incident revives memories of the 2024 CrowdStrike failure, which Microsoft estimated disabled 8.5 million Windows computers worldwide.

This one stems from Microsoft's own infrastructure.

Microsoft outage leaves Outlook, Teams, Copilot disrupted for 11 hours: Here’s what happened November 13, 2026.