Microsoft 365 Crawls Back to Life After a 24-Hour Outage

Microsoft 365 services including Outlook, Teams, and Copilot gradually returned after an outage that began around midday Thursday on the US East Coast. Initially reported in North America, the disruption spread to more than 70 countries, affecting businesses, governments, and tens of millions of users. Microsoft said the failure was technical, not the result of a cyberattack or artificial intelligence. Its preliminary explanation points to a problem introduced during an earlier network capacity upgrade that emerged after a recent network change. The company said it had fixed the underlying issue, was restoring service to remaining customers and regions, and would publish a full review after investigating what happened.

The outage disrupted government functions in countries including Japan and the United States, affected airlines’ communications with customers, and interrupted operations at hospitals and emergency services. Even after systems resumed, users could face delayed messages and a surge of notifications as services and supporting systems came back online. Microsoft extended email queue times to 48 hours to help ensure messages sent during the outage would eventually be delivered. The incident’s total impact may remain unclear, but it exposes the risks of relying on one provider for essential cloud services. As modern life depends on interconnected systems, a prolonged failure can reach far beyond delayed email.