Microsoft Resolves Worldwide Service Disruption, Dismisses Cybersecurity Breach Theory
Following a disruption that lasted more than 24 hours, Microsoft has successfully restored access to Teams, Outlook and additional Microsoft 365 applications, confirming the incident was not the result of a cyberattack.
According to Microsoft, the company has successfully brought Microsoft 365 services back online following a worldwide service disruption that impacted Teams, Outlook and various other applications for a period exceeding 24 hours, once again emphasizing that the incident was not the result of any cybersecurity breach.
The company announced on Saturday that it had successfully "restored service to the remaining impacted customers and regions," providing guidance to affected users to reference incident MO1550821 within the Microsoft 365 admin center for additional details.
In a statement released on Friday, Microsoft explained that the service disruption originated from an issue that was introduced during a previous network capacity upgrade, which subsequently surfaced following a recent modification to the network infrastructure. "This was a technical issue not related to cyber or AI/agents," the company stated clearly.
Microsoft reported that it had successfully resolved the root cause of the problem and proceeded with a gradual restoration of services, implementing stability verification procedures before advancing to each subsequent phase. The company issued an apology for the service interruption and committed to publishing a comprehensive post-incident report following the completion of its internal investigation and review process.
The service disruption commenced on Thursday, causing widespread interruptions to access for Exchange Online mailboxes and various functionalities associated with Teams, Outlook and Microsoft Copilot. Multiple government agencies across Japan, Singapore and the United States encountered significant email delivery and access problems, while integrations connecting Microsoft 365 with various AI assistant platforms were similarly impacted during the outage.
Representatives from OpenAI confirmed that the Microsoft 365 connector functionality in ChatGPT had returned to normal operations, while Anthropic similarly updated its status page to indicate that both its Microsoft 365 connector and the Claude for Outlook incident had been fully resolved.