Microsoft 365 Outage Hits Outlook, Teams and Copilot Worldwide

A widespread Microsoft service failure has disrupted email and artificial intelligence tools for users around the world, according to BBC Technology. Monitoring site Downdetector recorded almost 140,000 reports of trouble with Outlook at about 18:00 GMT on Thursday, with complaints coming from 74 countries.

Microsoft said a cyber-security incident did not cause the disruption. The company pointed instead to heavy strain on its infrastructure, saying that many servers dropped offline without warning and pushed extra traffic onto the machines still running.

Microsoft 365 products affected by what the firm described as connectivity problems include Teams, Outlook and Copilot, its AI assistant. Customers describe differing levels of access. Plenty cannot send or receive mail, open some files or check details in their calendar apps, while others report that Teams messaging and online meetings work as usual.

Repair attempts have largely failed so far. Microsoft initially said its remedies were not behaving as it had hoped, and on Friday morning it reported only slight progress. The company added that it keeps watching activity in each region to judge server health and work out how to add capacity.

Microsoft's website states that more than 430 million people use its 365 apps, and businesses across the world rely on them, so other services are likely to feel the effects. OpenAI, the maker of ChatGPT, said it was looking into a problem with its links to Microsoft's services that stopped some tools working properly. Anthropic also reported difficulties.

Public bodies have been caught up too. Singapore's government and Australia's spy agency both said the disruption reached them.

Troy Hunt, an Australian cyber-security specialist, told the BBC that Microsoft forms a huge share of the internet's underlying plumbing and that the episode shows how much work still depends on email. He said the failure blocks routine tasks such as arranging appointments, buying items that require verification and setting up or reaching accounts. Paul Spain of New Zealand advisory firm Gorilla Technology said firms had effectively lost a working day, leaving users frustrated.