Global Microsoft outage: Outlook, Teams and Copilot disrupted across 74 countries

Microsoft's most widely used workplace services have been hit by a major global outage. More than 12 hours after Outlook was knocked out and Teams and Copilot disrupted, the company itself says it has had only "marginal success" in restoring service. Users in 74 countries have been affected.

In a statement on its service health page early on Friday, Microsoft said it was monitoring activity across regions to assess server status and find ways to improve capacity. It said this includes reviewing server performance and confirming that developed patches have been applied and are working as intended after infrastructure reboots are completed.

Problems began at about 16:00 GMT on Thursday, when users began reporting that they could not access Outlook, its email platform. Within about an hour, the outage tracker Downdetector had logged reports from 74 countries and territories.

Microsoft first said it was investigating problems in the Americas, but later confirmed that users in any region could be affected. It said the affected infrastructure was experiencing elevated load across multiple regions, which was likely contributing to the connectivity errors. The company later said a number of servers had become unexpectedly unavailable, and that the elevated load had not been caused by an increase in traffic.

The disruption dragged on through the US working day and into the night. By Friday morning in Europe, it had still not been resolved, and servers Microsoft had restored were failing again.

By about 07:00 GMT on Friday, Downdetector had received at least 43,000 reports of problems with Outlook from users in 72 countries. The true number is likely far higher, since the figure only counts people who visit the site to report an issue. Microsoft has not confirmed the number of users affected.

Government systems in Singapore and Japan have been disrupted, as have communications at the Supreme Court of the Philippines. In Australia, the country's spy agency and federal police were among the organisations hit.

Outlook has been hit hardest. Users have reported being unable to open their mailboxes via the web, the app or mobile devices, and many emails that do go through have arrived late. Other services have been partly disrupted. The disruption has spread beyond Microsoft's own products, hitting integrations that other companies, including the AI firms OpenAI and Anthropic, rely on.

Microsoft has not published a root cause but said the outage was not the result of a cyberattack. Charles Lamanna, the company's executive vice president of Copilot, Agents and Platform, said in a post on X late on Thursday that there is no indication this is the result of malicious or cyber activity. On Friday, the company was rolling back a network change, but did not say whether that change was to blame.

Australia's Home Affairs Minister Tony Burke told a news conference in Sydney that Microsoft had also told him it did not believe it was dealing with a cyberattack. "They believe they are dealing in some ways similar to what we saw with respect to CrowdStrike where there is an update that has gone awry," Burke said.

Technology analyst and journalist Rupert Goodwins said the scale of the incident is impressive and that it is very embarrassing for Microsoft. Elevated load, he said, usually comes from one of two places: an external attack, or a faulty update to internal systems. Microsoft says an attack has not happened; and as servers come back up, they are immediately swamped by traffic from all the other servers desperate to talk to them, so it all falls down again, he explained.

Walter Pasquarelli, an affiliate researcher at the Bennett School of Public Policy at the University of Cambridge and an AI specialist, said about 430 million people use Microsoft services, and that what is known so far points first and foremost to a communication risk. Some servers started failing automated health checks, he said, and traffic then moved to other servers, which became overloaded — like a highway suddenly going from four lanes to two. The evidence so far, he said, points to a technical failure.

Microsoft has not given a timeline for full recovery. It has said that as capacity returns, users may see service come back gradually as their apps reconnect, rather than all at once. There is little users can do themselves, as the problem lies with Microsoft's servers rather than their own devices. The desktop version of Outlook may still show emails already downloaded, while Teams chats and calls have largely continued working.

This is not Microsoft's first major outage this year. In January, Microsoft 365 went down across North America for almost 10 hours; the company blamed heavy service load combined with reduced capacity during maintenance. In late August, thousands of Outlook users worldwide were locked out of their mailboxes.

Other tech companies have suffered similar failures. In October 2025, an Amazon Web Services outage took down a large number of websites and apps. And in July 2024, a faulty software update from the cybersecurity firm CrowdStrike crashed computers around the world, cancelling flights, disrupting hospitals and causing billions of dollars in losses.