Microsoft Azure and Microsoft 365 outage caused by maintenance bug
Service Disruption
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A maintenance-system bug triggered a massive Microsoft outage that disrupted access to Azure and Microsoft 365 services for customers tied to West US infrastructure. The disruption affected core collaboration and admin tools, including OneDrive, SharePoint Online, Teams, and the Microsoft 365 Admin Center. Microsoft reverted the networking change and said affected services had recovered by 3:41 PM ET. The event shows how an automated maintenance workflow can create broad availability and functionality failures across a large cloud stack.
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Timeline
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24.07.2026 18:41 2 articles · 4h ago
Microsoft Azure and Microsoft 365 outage caused by maintenance bug
Initial DisclosureBy 10:44 AM ET, Microsoft was seeing a large-scale route churn problem in its WAN after routine maintenance in West US Azure. Early rerouting helped some customers, but the outage remained active while engineers traced the route removals to the maintenance workflow.
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- Microsoft blames massive Microsoft 365 outage on maintenance bug — www.bleepingcomputer.com — 24.07.2026 18:41
- Microsoft blames massive Microsoft 365 outage on maintenance bug — www.bleepingcomputer.com — 24.07.2026 18:41