with repair efforts so far largely unsuccessful. Microsoft says the issue was not caused by a cyber-security incident.

What's affected: Microsoft 365 services—Teams, Outlook, and the Copilot AI software—are experiencing "connectivity problems." Many users cannot send or receive emails or view certain files and calendar details, though some can still use Teams messaging and meetings. The full scale is unknown, but Downdetector logged 140,000 Outlook reports from 74 countries on Thursday evening; the true figure is likely much higher, given more than 430 million Microsoft 365 users worldwide. The disruption has rippled outward: OpenAI and Anthropic both reported knock-on problems, and governments, courts, hospitals, police, schools, and GP surgeries across the US, Canada, Japan, Australia, and the UK have been affected.

Microsoft's explanation: The company attributed the outage to "elevated load"—a large number of servers became "unexpectedly unavailable," pushing extra traffic onto the remaining servers and straining them. On Friday morning Microsoft reported "early signs of stabilisation" and progress toward restoring platforms, though it warned "some intermittent issues may continue." Earlier it admitted its fixes were "not taking as expected."

Expert reaction: Australian cyber-security expert Troy Hunt noted that Microsoft is a "massive part of the internet backbone," and the outage shows how critical email remains—affecting not just work but appointments, verified purchases, and account access. Former Skype and Uber engineer Gergely Orosz called it potentially the "most disruptive" business email outage "of all time," saying he cannot recall one taking this long to resolve. Paul Spain of Gorilla Technology said firms had effectively "lost a business day." (BBC)