Microsoft 365 Outage History

Some Microsoft 365 admins were unable to view usage reports in the Microsoft 365 admin center due to a code issue in a recent backend infrastructure migration. The incident affected the reports API endpoint, preventing admins from accessing usage analytics and reporting data. Microsoft identified the root cause, developed and deployed a fix through a staged rollout, with the issue being resolved for the majority of users after approximately 80 hours.

Microsoft 365 users worldwide experienced intermittent failures when accessing Exchange Online mailboxes due to faulty authentication components and underperforming SQL infrastructure. The issue affected users globally who were routed through the impacted infrastructure, preventing them from accessing their mailboxes via various connection methods. Microsoft deployed a fix to address the faulty authentication components and restarted affected infrastructure to restore service after 9.2 hours.

Microsoft 365 services in South America experienced a 6.6-hour outage caused by intermittent network connectivity issues and a fiber connectivity disruption between regions. Users reported email delivery delays, intermittent connection disruptions, 503 errors when accessing Outlook and Teams, and inability to access SharePoint sites and OneDrive content. Microsoft resolved the issue by rerouting traffic to alternate network paths, bringing additional network resources online, and implementing infrastructure optimizations.

A code regression in a Microsoft 365 service update caused some users in Europe to receive "Page not found" errors when accessing Exchange Online through Outlook on the web for 1.7 hours. Users reported being repeatedly logged out of Microsoft services during the incident. Microsoft resolved the issue by rolling back the problematic update, while users could access their email through Outlook desktop or mobile clients as a workaround.

Microsoft OneDrive users experienced issues loading the search bar functionality for 3.3 hours. The incident affected any user attempting to use the search feature in OneDrive, with some users also reporting Exchange 365 not loading while other admin portals remained functional. Microsoft resolved the issue by identifying and rolling back a recent change that was contributing to the problem.

Users experienced issues loading the search bar in SharePoint Online sites, preventing them from using search functionality across the platform. Microsoft identified and rolled back a recent change that was contributing to the problem after reproducing the issue in their environment. The incident lasted 4.1 hours and was resolved through the rollback while Microsoft monitored service health to confirm the fix.

Microsoft 365 Copilot Chat users experienced issues accessing links to other apps, receiving errors or encountering pages that never loaded when clicking on app links generated by Copilot prompts. The issue affected Copilot Chat across multiple Microsoft services including Teams, Word, Excel, PowerPoint, Outlook, and OneNote. Microsoft identified the root cause as a code error introduced during an update to increase URL routing capacity, developed a fix, and began deployment, though the rollout progressed slower than anticipated with an extended timeline for full resolution.

SharePoint Online users experienced search functionality failures where searches returned no results, caused by unexpected traffic spikes and search request queuing that overwhelmed a subset of service infrastructure. Microsoft resolved the issue by redirecting and rebalancing traffic to alternate infrastructure while optimizing search request handling capacity. The incident lasted approximately 523 hours (about 3 weeks) and was resolved after traffic optimization efforts successfully remediated the impact.

Microsoft 365 users experienced issues accessing web-based services when using Google Chrome Version 147, with problems including missing UI elements, failed page loads in the admin center, and inability to open Excel/PowerPoint files through web pages. The issue was isolated to Chrome browsers, while Microsoft Edge and other browsers remained unaffected. Microsoft resolved the incident by updating authentication components across service endpoints, with users needing to refresh their browser pages to experience relief.

An authentication component misconfiguration disrupted the Autodiscover flow for Exchange on-premises connections, preventing some users from accessing email messages through Outlook Mobile for 71.9 hours starting April 10, 2026. Microsoft identified the root cause and was developing a fix to correct the misconfiguration that was blocking Outlook Mobile from automatically establishing access for affected users. The incident had minor status and impacted users attempting to connect to Exchange on-premises environments through the mobile application.