Key facts
- Microsoft confirmed a widespread, multi-hour outage affecting Outlook and its Exchange Online service.
- Users experienced email delays, sending and receiving failures, and authentication errors.
- The company identified an issue with an authentication component as the cause.
- Microsoft is testing a remediation strategy to address the outage.
Microsoft confirmed on Monday a widespread, multi-hour outage impacting its Outlook service and cloud-hosted Exchange Online platform. Users reported experiencing email delays, failures in sending and receiving messages, issues with mailbox searches, and authentication errors. The company stated it identified a problem with an "authentication component" contributing to the degraded functionality. Microsoft is currently testing a remediation strategy on a portion of its infrastructure to determine its efficacy before a broader rollout. The outage highlights the continued reliance of the business world on email services like Outlook and Exchange.