Microsoft’s global 365 outage stretched past 10 hours as the company said traffic protocol adjustments, rerouting and strategic traffic blocking produced only partial recovery across regions and “aren’t resulting in sustained recovery.” The disruption hit Australia’s spy agency and federal police, Indian airline IndiGo’s email support, a US state government and two Michigan hospital systems. Microsoft executive Charles Lamanna said “there is no indication this is the result of malicious or cyber activity.”
The incident began at 16:17 UTC Thursday on Exchange Online after servers unexpectedly went offline and overwhelmed a core process on remaining infrastructure, with restored servers becoming unresponsive again once traffic resumed. The Verge’s Tom Warren said a rollout spiked server CPU usage, forcing racks into maintenance mode and causing cascading failures, while commentators noted the breakdown followed Microsoft’s Oct 26 buyout offer to about 60,000 employees.
Outage reports on Downdetector spread to 74 countries and territories within an hour and reached 19,650 per minute across five Microsoft services, compared with fewer than 15 on an average Thursday. Outlook reports peaked at more than 2,000 times normal levels and topped 130,000 total reports, alongside disruptions to Teams, Copilot, OneDrive, SharePoint, the Defender XDR security platform and Microsoft connectors in OpenAI and Anthropic tools.
