Microsoft's Outlook Faces Multi-Hour Global Outage

Microsoft confirmed on Monday that its Outlook email service was experiencing a multi-hour outage, affecting users worldwide.

The issue, which started around 11:30 AM ET, impacted Exchange Online, the cloud-hosted platform for business email, calendar, contacts, and tasks.

According to Microsoft's post on X, the problem was caused by an authentication component issue, and a remediation strategy was being tested with a portion of the infrastructure to determine its efficacy.

Users reported experiencing degraded functionality, including delays and failures in sending or receiving messages, as well as authentication errors and mailbox operations issues.