Microsoft 365 outage stretched past a day as server losses overloaded remaining capacity

Starting 16:17 UTC on 12 November 2026, many users lost access to Exchange Online, the Microsoft 365 service that holds Outlook mail, calendars and contacts. Microsoft later reported that the problem was not a surge in users but a growing number of servers dropping offline, which pushed their workload onto the surviving machines. Eighteen other Microsoft 365 services, including Teams, Copilot and Intune, were soon listed as affected. By 00:31 UTC on 14 November the incident was marked as recovering rather than closed, with Microsoft still clearing a backlog of delayed email. The company has not yet published a root cause and has promised a Post-Incident Report.