Microsoft 365 Outage: Outlook, Teams and Copilot Down Worldwide as Reports Near 140,000
Millions of people started their Friday without email. Microsoft 365 — the software that runs Outlook inboxes, Teams meetings and the Copilot assistant for offices across the world — broke down on Thursday evening, and well into Friday it still was not working properly.
At the worst point, Downdetector, the site that tracks service failures, logged nearly 140,000 reports of Outlook problems in a single hour. The complaints came from 74 countries. By Friday morning in Pakistan, Microsoft was describing only “early signs of stabilisation”. The fixes, it admitted, were “not taking as expected”.
Microsoft 365 outage: what went wrong
The failure began at 16:17 UTC on Thursday — 9:17pm Pakistan time — when Exchange Online users found they could no longer open their mailboxes. Exchange Online is the engine behind Outlook email, so when it stopped, inboxes froze everywhere: on the web, on desktop apps, on phones.
Microsoft opened a formal incident for the mailbox failure, tracked as EX1550543, and a wider one for the whole suite, MO1550821. Within two hours the problem had spread beyond email. Teams calendars and scheduling stopped working. SharePoint features that depend on Exchange faltered. Copilot, Microsoft’s AI assistant, went down with them. Planner, To Do, Intune, Purview, Power BI and parts of Defender were all listed as affected at various points. Even Xbox Live users reported problems through the night.
What caused it? Microsoft has not published a confirmed root cause yet, and it says it may not do so until the incident is closed and a full post-incident report is ready. What it has said is this: a large number of its servers became “unexpectedly unavailable”, apparently after failing automated health checks, and the servers that were left could not carry the load. In a later update the company said a process on the affected servers — the one that sets up secure connections — was becoming overwhelmed, and the servers stopped processing requests. Traffic was not the problem. Microsoft has ruled out a surge in users. And it says there is no sign of a cyberattack. The BBC, which has been covering the outage live, reports there is no indication it was caused by malicious activity.
How far the Microsoft 365 outage spread
The numbers only tell part of the story. Behind the 140,000 reports were surgeries that could not reach patients, pharmacies waiting on prescriptions, schools, police forces and a parliament. The BBC said its own corporate email was down. Hospitals and airports in Britain were among the services affected, according to the broadcaster’s reporting.
In the United States, the outage reached into corporate results season. Workhorse Group, an electric vehicle maker, postponed its third-quarter earnings report from Thursday to Monday 16 November because its systems were caught in the failure.
For Pakistan, the timing was awkward in a different way. The outage began late on Thursday night local time and ran straight into Friday’s working day for anyone whose office runs on Microsoft 365 — and in a country where Outlook and Teams are the default tools of banks, telecoms, NGOs and startups, that is a lot of offices. Google Trends showed the Microsoft 365 outage among the fastest-rising searches in Pakistan on Friday, with more than 100,000 searches.
When will Outlook and Teams be back?
That is the question Microsoft has not answered. Through Friday its updates used careful language: “marginal success”, “incremental improvement”, “service health remains variable and capacity has not yet fully returned to baseline”. Traffic was being “carefully reintroduced” to the repaired servers. Some users found their mail working again, only for it to fail a second time. As of Friday morning, more than 13 hours after the first failures, Microsoft had given no time for full recovery.
If you are still locked out, the first thing to know is that the problem is not your computer, your password or your office Wi-Fi. Do not reset anything. The fault sits on Microsoft’s side, and the place to watch is the company’s own status page at status.cloud.microsoft, or the Service health section of the Microsoft 365 admin centre, following incidents EX1550543 and MO1550821. Microsoft’s support account on X, @MSFT365Status, is posting updates as they come. Admins can also check whether their own tenant is among those recovering, since Microsoft has said recovery has been uneven — some regions and servers came back while others went down again.
A reminder of how much rides on one suite
Outages are not new. What makes this one sting is the sheer breadth of it — email, calendars, meetings, documents, AI help and device management all failing at once, in every region, for most of a working day. Microsoft 365 is used by hundreds of millions of people, and for many businesses there is no second system waiting to take over. When the suite goes dark, the office does too. Nvidia’s leadership shake-up rattled US tech stocks this week, but that was a market story; this one hit the tools people actually work with.
That concentration is exactly why the post-incident report will matter. Microsoft has promised one once the incident closes. Until then, the company is still, in its own words, working to get capacity back to normal — and millions of inboxes are waiting.
Sources: BBC News live coverage, 13 November 2026; Reuters, 13 November 2026; Microsoft 365 Status updates (incidents MO1550821 and EX1550543), 12–13 November 2026; Downdetector.