Microsoft outage drags past 10 hours as Outlook, Teams and Copilot stay down in 74 countries
Building 92 of the Microsoft campus in Redmond, Washington, home to the Microsoft Visitor Center. (File photo)
Millions of people around the world have been unable to open their email since Thursday evening, as a major Microsoft outage stretched into Friday afternoon. Outlook, Teams, Copilot and several other Microsoft 365 applications were affected, and within an hour of the disruption starting it had spread to 74 countries and territories. Outage tracker Downdetector recorded nearly 140,000 reports around 18:00 GMT on Thursday, the peak of the complaints.
What went wrong
Microsoft says the problem is centred on Exchange Online, the cloud service that handles email and mailbox access for Microsoft 365 users. A large number of servers unexpectedly became unavailable, failing automated health checks, while a core process that establishes secure connections became overwhelmed. The load then cascaded onto the servers still running, and the problem spread. The company has made clear this was not caused by a sudden surge in traffic, and there is no indication of a cyberattack.
Why the fix is taking so long
Microsoft has admitted that its first attempts to restore service are “not taking as expected”. Engineers are now pursuing alternate workstreams and testing a configuration change on a subset of servers before rolling it out more widely. No timeline has been given for full recovery. Executive Vice President Charles Lamanna wrote on X that the company regrets the disruption and is working to address it, confirming there is no indication the outage is the result of malicious or cyber activity.
Who was hit
Outlook was the worst affected, with users unable to send or receive emails or even load their inboxes. Teams and Copilot were hit alongside Word, Excel, PowerPoint, SharePoint and OneDrive. The disruption also reached OpenAI and Anthropic’s artificial intelligence services through their Microsoft 365 connectors. Offices, government departments and businesses have faced interrupted daily work since Thursday, with the outage now approaching the 12-hour mark.
