The global outage affecting Microsoft 365 services continues as the company struggles to implement a permanent fix. The disruption, which has persisted for over ten hours, has seen servers becoming unresponsive shortly after being restored, impacting critical user access worldwide.
Timeline of the Outage
The service disruption started on November 12, 2026, initially affecting Exchange Online access in the Americas. The issue rapidly expanded to impact users of Outlook, Teams, SharePoint, Copilot, and Microsoft Defender XDR across various regions. Despite attempts to restore services, Microsoft has yet to provide an estimated timeframe for a complete resolution.
The incidents, labeled EX1550543 and MO1550821, are being tracked in the Microsoft 365 admin center. Microsoft is undertaking multiple strategies simultaneously to address the core issues and return its infrastructure to normal operations.
Technical Challenges and Responses
One of the main challenges Microsoft faces is the inability to maintain server stability after a restart. According to updates from Microsoft’s 365 Status account, servers often become unresponsive once user traffic is reintroduced. Engineers are currently analyzing diagnostic data to identify the underlying cause of this behavior.
To manage the situation, Microsoft has introduced several fallback measures. These include temporarily limiting specific types of traffic to the affected servers, rebuilding servers using previous configurations, and rerouting traffic to alleviate pressure on the infrastructure.
Impact and Recovery Efforts
Despite these measures, full recovery remains elusive. Partial service restoration has been noted in regions where traffic management strategies have been applied, but these are not yet stable solutions. Microsoft continues to monitor performance closely, making gradual adjustments to improve service stability across all regions.
Downdetector recorded over 120,000 reports of Outlook issues at the height of the outage, with affected users spanning 74 countries. The impact extended beyond Microsoft services, affecting third-party platforms like OpenAI and Anthropic. Additionally, companies such as Workhorse Group have had to postpone scheduled announcements due to the disruption.
Guidance for Administrators
Administrators are advised to track updates using incident IDs EX1550543 and MO1550821 in the Microsoft 365 admin center. It is recommended that they avoid taking local troubleshooting measures, such as resetting passwords or altering tenant settings, as these actions are unlikely to resolve the issue.
Administrators should also inform users about potential phishing scams exploiting the outage and prepare for possible delays in mail delivery as services begin to recover. Microsoft has assured that the outage is not due to a security breach and that efforts to restore full service remain a top priority.
