Massive Microsoft outage disrupts businesses, government agencies worldwide

A network glitch caused Microsoft's services to be offline for businesses and government agencies across more than 70 countries on Thursday around 12:35 p.m. EST. The Exchange Online platform, which stores employees' inboxes and calendars, was particularly affected. Microsoft has not yet fully restored its infrastructure. However, deployments of Exchange Server, a version of the platform run on-premises, remain unaffected.

The outage disrupted Microsoft Teams and Microsoft Copilot 365 features that rely on Exchange inbox data. Intune, a tool for managing employee devices, also experienced issues. Companies worldwide, including Workhorse Group Inc., Maersk, and Euronext, reported communications problems. U.S. municipalities and courts faced technical difficulties, and the National Pharmacy Association warned of potential delays in prescription processing.

Hospitals, public transportation agencies, and schools were also impacted. The Downdetector outage tracking service received reports from hundreds of thousands of users. Microsoft patched an "upstream authentication/routing configuration" module and reported positive results shortly after the incident. The Asia Pacific, North America, and Europe regions regained service access within a few hours.

Microsoft explained that the incident was caused by an issue during a network capacity upgrade, not a cyberattack or AI agents. The company is still restoring service to remaining customers and regions, monitoring the backlog of emails to prevent data loss, and plans to release a detailed technical report upon full restoration.