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[TECHNOLOGY] · United States, Germany, Austria, Türkiye, Ecuador · 53 sources

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Microsoft Outlook and Exchange Online suffer global outage

A massive global outage affecting Microsoft Outlook and Exchange Online disrupted email services for millions of users on August 31, 2026. The incident, tracked as EX1464935, caused widespread issues including login failures, difficulties sending or receiving emails, mailbox synchronization errors, and application freezing.

Microsoft identified the root cause as a technical error within a central authentication and connectivity component of the Exchange Online cloud infrastructure. The disruption also impacted other Microsoft 365 services, including Teams, OneDrive for Business, SharePoint Online, Microsoft Purview, and Microsoft Defender XDR.

Downdetector reported tens of thousands of user complaints during the peak of the outage. Microsoft has since initiated remediation efforts, rolling out updates to affected servers to restore services. While telemetry data indicates a gradual recovery and systems are beginning to stabilize, some users may still experience delays in email delivery and mailbox synchronization as backlogs are processed.

Entities

Downdetector · Exchange Online · Microsoft · Microsoft 365 · Microsoft Outlook · Outlook

Claims

What the coverage asserts, and how many sources carry each claim.

Sources

11 days ago
Microsoft mit E-Mail-Störung [www.it-business.de]
11 days ago
Microsoft Outlook Is Down [au.lifehacker.com]
11 days ago