Microsoft 365 Outage Disrupts Outlook, Teams Scheduling and Copilot

A Microsoft 365 outage disrupted Outlook email, Teams calendar scheduling and Microsoft 365 Copilot across multiple regions on Thursday, leaving some users unable to access mailboxes or schedule meetings.

The disruption began around noon ET on Nov. 12. Outlook users could have trouble sending or receiving messages, and delivery could be delayed. Teams chats and online meetings were largely working, but calendar features that rely on email services could fail. Copilot could stop responding or be unable to read email and calendar data. Files stored directly in SharePoint remained accessible, though some other services had limited functions.

Microsoft said overloaded processing for encrypted connections on affected servers had stopped them from handling requests. The company was preparing a configuration change, testing it on some servers before broader use alongside server restarts. It had also begun reversing a recent network configuration change.

At 8 p.m. ET (01:00 UTC Nov. 13), Microsoft's service status page still showed the issue as unresolved. A further update was scheduled for 9 p.m. ET (02:00 UTC Nov. 13).