A broad Microsoft 365 outage began around 13:25 US Eastern time on November 12, 2026, affecting Outlook, Teams, Copilot, OneDrive and other services. Microsoft’s preliminary investigation attributed elevated load mainly to unexpected server unavailability rather than a traffic surge, placing pressure on the remaining infrastructure. The company said there were no signs or evidence of a malicious cyberattack and paused deployments, released memory, adjusted traffic routing and restarted servers. Eligible enterprise customers may request service credits under their service-level agreements. Under the April 2026 agreement, credits may reach 25%, 50% or 100% when Exchange Online’s monthly availability falls below 99.9%, 99% or 95%, respectively.