Microsoft confirms global outage resolved, rules out cyberattack

Microsoft said it had restored Microsoft 365 services after a global outage disrupted Outlook, Teams and other applications for more than 24 hours, reiterating that the disruption was not caused by a cyberattack.

On Saturday, the company said it had “restored service to the remaining impacted customers and regions,” directing customers to incident MO1550821 in the Microsoft 365 admin center.

On Friday, Microsoft said that the outage stemmed from a problem introduced during an earlier network capacity upgrade that emerged after a recent network change. “This was a technical issue not related to cyber or AI/agents,” the company said.

The company said it had addressed the underlying issue and restored services gradually, checking stability before proceeding to the next stage. Microsoft apologized for the disruption and said it would publish a full post-incident report once its review is complete.

The outage began Thursday, disrupting access to Exchange Online mailboxes and features linked to Outlook, Teams and Microsoft Copilot. Government agencies in Japan, Singapore and the United States experienced email problems, while connections between Microsoft 365 and AI assistants were also affected.

OpenAI said the Microsoft 365 connector in ChatGPT was operating normally again, while Anthropic also marked its Microsoft 365 connector and Claude for Outlook incident as resolved.

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