Microsoft rules out malicious activity in global Outlook and Teams outage

Microsoft said it was not aware of any malicious activity behind a global outage that disrupted Outlook, Teams and Copilot worldwide.

Outage scope and impact

The outage affected Microsoft 365 services in 74 countries and territories, according to outage tracker Downdetector. Downdetector logged nearly 130,000 US reports of Outlook problems shortly after 1 p.m. EST (1800 GMT). Users reported trouble sending and receiving email, and some said the program was entirely inaccessible. Teams and Copilot were also affected.

Microsoft 365 connectors used by OpenAI and Anthropic were impacted, with both companies saying tools were not working as expected.

Microsoft's response

Microsoft said a portion of its infrastructure was experiencing elevated load across multiple regions, which was likely contributing to connectivity errors. The company said some servers stopped working, leaving the remaining servers overloaded.

Microsoft said it paused all deployments, moved additional traffic off the affected infrastructure, and restarted affected servers. Some restarted servers stopped responding again once traffic returned.

The company said changes applied to improve serviceability were not taking as expected, and it was identifying alternate workstreams to increase capacity.

Microsoft said it was observing limited recovery as it sought to route user traffic away from affected servers. It added that as capacity is restored, users may experience a gradual recovery as their clients reconnect.

Statements on cause

Microsoft executive Charles Lamanna said in a post on X: "We regret that today’s outages caused disruptions for our customers, and we are working to address the issue. We will continue to share more information as soon as we have it, and for now I can confirm that there is no indication this is the result of malicious or cyber activity."

Microsoft also said on X: "As of now, we are not aware of any malicious activity that is causing this incident. We will continue to treat this incident with urgency and priority until full resolution."

The company said it was not aware of malicious activity that could have caused the outage.

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Sources

• dw.com: Microsoft rules out 'malicious activity' in global outage
• theherald.co.za: Microsoft battles global Outlook outage, rules out signs of malicious activity | The Herald
• news.cgtn.com: Microsoft rules out cyberattack as global Outlook outage disrupts services in 74 countries
• economictimes.indiatimes.com: Microsoft rules out cyberattack as global outage hits Outlook, Teams and Copilot - The Economic Times
• en.politis.com.cy: Microsoft Global Outage Disrupts Outlook, Teams and Other Services
• tokenpost.com: Microsoft Says Cyberattack Did Not Cause Global Microsoft 365 Outage | TokenPost

This article was drafted with AI assistance and checked against the sources above. Company claims are reported as claims. Cover image is AI-generated.