A widespread outage has hit Microsoft platforms, with a fix "not taking as expected".
Outlook and Teams have been impacted by the global outage, with hundreds of thousands of users reporting issues on tracker Downdetector.
AI assistant Copilot and wider Microsoft 365 services have also been affected.
Microsoft executive vice president Charles Lamanna ruled out a cyberattack and said the firm was "working to address the issue".
In a service update, Microsoft said: "We've monitored the status of the changes applied to improve serviceability and confirmed that change is not taking as expected.
"We're identifying alternate workstreams that can be applied to increase capacity in the face of sustained traffic management imbalances."
Earlier, it said parts of its infrastructure were "experiencing elevated load".
The outage has caused issues for several governments, with officials in Japan, India and Australia reporting problems.
Japan's deputy chief cabinet secretary Masanao Ozaki said the government's IT infrastructure had been impacted and ministers were "keeping a close eye on the developments."
The Western Australian state government said Microsoft is "prioritising life, safety and government services".
(c) Sky News 2026: Microsoft suffers global outage - as fix not going 'as expected'
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