Microsoft 365 outage hits Outlook as reports pass 130,000
A Microsoft 365 outage knocked out Outlook, Teams and other services on Thursday, with more than 130,000 problem reports logged by early afternoon.
Outage hits email and chat at midday
Microsoft 365 went down on Thursday, knocking out Outlook, Teams and other services for thousands of users in the United States, according to outage tracker Downdetector. The problems began shortly before 1 p.m. ET, and more than 130,000 people had reported Outlook issues by 1:27 p.m. ET, Reuters reported, citing Downdetector data.
Word, Excel, PowerPoint, SharePoint, OneDrive and the AI assistant Copilot were also affected, CNBC reported. Microsoft confirmed the problems in a post on X, saying it was investigating reports of users having trouble reaching Exchange Online mailboxes through several connection methods in the Americas.
Servers, not traffic, behind the failure
Microsoft said the elevated load on its systems was not caused by more people using the services. "We determined the elevated load isn't driven by an increase in traffic, but by a number of servers being unexpectedly unavailable," the company said in a status update, adding that the missing servers were straining the infrastructure that remained.
The company said a component that checks server health had failed, and it launched a restart of the affected servers. It also paused deployments and began moving traffic to other systems while it worked to restore service, according to its status updates.
- Outlook reports by 1:27 p.m. ETMore than 130,000
- Services hitOutlook, Teams, 365
- Outage beganShortly before 1 p.m. ET
- Admin incidentEX1550543
- CauseServers unexpectedly unavailable
Reports spread beyond Microsoft
Users of Amazon Web Services and Google also reported problems on Downdetector during the same period, CNBC reported. The companies' own status pages showed no matching widespread outage, suggesting the reports reflected confusion during the Microsoft failure rather than separate breakdowns.
Earlier in the day, Microsoft had fixed a separate Teams disruption affecting users in North America, Reuters reported. The company later said the Microsoft 365 problem could also affect service connectivity for users in other regions.
What to watch next
Microsoft told administrators to follow the incident in the Microsoft 365 admin center under EX1550543. The company had not declared the incident over in its afternoon updates, and said it was still restarting servers and shifting traffic off the affected systems.
The outage was a reminder of how much daily work runs through a single provider's cloud. Email, meetings, documents and chat all went down together, and the fix depended on Microsoft's own servers coming back online.
