Microsoft Outlook.com outage causing sign-in failures
Service Disruption
Summary
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Microsoft's Outlook.com is experiencing an ongoing outage that is blocking sign-ins and mailbox access, leaving some customers unable to use email normally. The disruption has produced thousands of user reports and is being labeled service degradation rather than a full shutdown. Microsoft says it is reverting a recently introduced change while it investigates the problem and monitors service telemetry. The outage's full scope and root cause remain undisclosed.
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Timeline
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27.04.2026 15:03 1 articles · 2mo ago
Microsoft Outlook.com outage causing sign-in failures
Initial DisclosureThe disruption emerged more than three hours before the latest update and quickly caused **login problems**, **connection issues**, and mailbox access failures for **Outlook.com** users.
Show sources
- Microsoft says Outlook.com outage is causing sign‑in failures — www.bleepingcomputer.com — 27.04.2026 15:03