Microsoft 365 is slowly returning to normal after a sprawling outage knocked Outlook, Teams, Copilot, and other workplace tools offline across multiple regions. The disruption began Thursday and continued into Friday, leaving users struggling to send email, access calendars, join conversations, and retrieve files. Microsoft services are beginning to recover, but the company has warned that intermittent failures and delayed messages may continue.
The incident, identified in Microsoft’s admin center as MO1550821, affected Exchange Online along with Teams, SharePoint Online, Microsoft 365 Copilot, and Defender XDR. The company initially described the problem as elevated infrastructure load, then said several servers had unexpectedly become unavailable, putting additional strain on the systems that remained online. Microsoft paused deployments, redirected traffic, and began returning affected servers to service. BleepingComputer’s timeline of the incident records the main Microsoft 365 disruption as beginning at 1:26 p.m. Eastern time Thursday.
The failure reached well beyond ordinary office inboxes. Staff at the U.S. House of Representatives were affected, while health care providers, schools, businesses, courts, and government agencies reported trouble communicating through Microsoft’s cloud tools. The Associated Press said the outage also interfered with police crime reporting, court operations, and other services that depend on Microsoft 365. The breadth of the impact highlights how deeply a single productivity platform has become embedded in public institutions and everyday infrastructure.
There was also a separate Teams incident earlier Thursday affecting users in North and South America. That disruption lasted roughly an hour and was attributed to resource contention that prevented Teams from processing messaging requests normally. Microsoft has said that earlier incident was resolved, but it has not established whether it was connected to the larger Microsoft 365 failure.
Recovery has been gradual rather than instantaneous. Microsoft said email access and delivery performance were improving across more of its infrastructure, while warning that some customers could still face connection errors as mitigation continued. Delayed messages have begun arriving for some Exchange users, and Microsoft extended its email timeout window to 48 hours while it worked through queues and backlogs. That means a service appearing online does not necessarily guarantee that every missing message, calendar item, or collaboration feature has caught up yet.
For users, the practical next step is patience: avoid repeatedly resending messages that may still be queued, check Microsoft’s service-health dashboard through an administrator when possible, and use alternate communication channels for urgent business or medical needs. The outage is a reminder that cloud convenience also creates concentration risk; when Exchange Online falters, the damage can ripple through email, meetings, identity systems, file access, and AI assistants at the same time.
