Overview
- A global outage that began on Thursday, November 12 knocked Outlook, Teams, Copilot and other Microsoft 365 services offline and produced roughly 130,000–140,000 user reports at peak.
- Microsoft said a network capacity upgrade introduced a fault that left a number of servers unavailable, which created elevated load and caused a key server process to stop responding.
- Engineers redirected traffic, restarted servers and suspended deployments as initial fixes failed to hold, and Microsoft now says it has addressed the underlying issue and is restoring remaining regions.
- The disruption forced police, hospitals, courts and businesses to use backup procedures, delayed corporate earnings calls and affected AI connectors used by OpenAI and Anthropic.
- Microsoft has found no sign of a cyberattack, is monitoring recovery, and has pledged a full post-incident review while customers assess operational and insurance impacts.