Microsoft 365 outage enters second day with gradual recovery underway
Multiple Microsoft services including Outlook, Teams, and SharePoint remain affected by an authentication misconfiguration, though the company reports improving conditions after mitigation efforts.
What happened
Microsoft experienced a multi-day outage beginning Monday affecting Exchange Online and multiple Microsoft 365 services due to a misconfiguration in core authentication components. The issue prevented authentication from deploying properly to a portion of infrastructure, causing email delays and failures, authentication issues, and access problems across Outlook, SharePoint, Copilot, Teams, Purview, Defender XDR, the Microsoft 365 Admin Center, and Universal Print. Microsoft identified the problem, reviewed recent changes, tested mitigations, and began rolling out fixes. By Monday evening, mail flow was improving though search functionality remained degraded; by early Tuesday morning, search functionality showed improvements. As of Tuesday, the company reported positive telemetry indications and improving service availability but had not declared full recovery, entering a period of extended monitoring.
Context
The outage affected core Microsoft productivity and collaboration services relied upon by millions of enterprise and business customers. The root cause—a misconfiguration in authentication components—impacted not just email but services dependent on the same authentication layer, amplifying the scope of disruption. The multi-day resolution timeframe underscores the complexity of diagnosing and remediating infrastructure-level issues affecting distributed systems, and the need for staged rollouts of fixes rather than immediate restoration.