Microsoft 365 faced a widespread global service disruption for a second day, affecting several of its core productivity and collaboration services. The outage affected Microsoft Teams, Exchange Online, OneDrive, SharePoint Online, and Microsoft 365 Copilot.
Microsoft’s incident report, identified as MO1465074, remains ongoing. The tech giant said, “The disruption began at 3:08 pm UTC on August 31 and stems from an issue in a core authentication configuration used across multiple Microsoft 365 services.”
The disruption created major issues across Microsoft’s cloud-based services. Exchange Online users reported difficulties sending and receiving emails, accessing mailboxes and searching mailbox content.
Microsoft made a post on X at 12:01 p.m. ET, saying, “ Service to Exchange Online had been disrupted. Exchange Online is a cloud-based enterprise service that delivers email, calendar, contacts, and tasks.”
Microsoft further explained that mail connectivity reflected widespread recovery. However, some organisations might continue to experience delays as backlogged messages are processed.
Microsoft also said, “ The root cause of the outage is an issue within a core authentication configuration used by multiple Microsoft 365 services. The status page reported Service degradation for Microsoft 365 Business or Enterprise.” The problems also affected other services such as:
OneDrive for Business
SharePoint Online
Exchange Online
Microsoft Teams
Microsoft Purview
Microsoft Defender XDR
Microsoft 365 Admin Center
Currently, Microsoft is actively testing a remediation strategy. The company is restarting affected infrastructure and reapplying a targeted fix to the authentication component.
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