Microsoft Services Outage Affects Email, Teams and Cloud Apps

Microsoft services experienced a global disruption beginning Thursday at approximately 6:15 p.m. GMT, leaving users across 74 countries unable to access email, messaging, and cloud-based applications.

The outage, which affected Microsoft 365, Outlook, Teams, and Copilot, persisted into Friday as the company struggled to stabilize its backend infrastructure.

Monitoring service Downdetector identified a sharp rise in user reports from the United Kingdom and Ireland before the outage spread globally to the Americas, Asia, and Africa, RTÉ reported. By Friday morning, the disruption remained active for many, with thousands of users reporting issues with inbox access and connectivity, according to The Times of India.

Microsoft confirmed the incident was not the result of malicious activity. “As of now, we are not aware of any malicious activity that is causing this incident,” the company said. The tech giant initially attributed the instability to servers failing automated health checks, though subsequent attempts to isolate infrastructure and reroute traffic failed to provide the expected relief, according to The Register.

Kevin O’Loughlin, of the Irish IT firm Nostra, compared the server failure to closing lanes on a motorway, where the loss of capacity places unsustainable pressure on remaining systems.

Global Impact on Organizations

The service failure disrupted operations for various government and private entities. In Ireland, the Health Service Executive (HSE) reported that email services were not transmitting, though video conferencing facilities remained intermittently functional, RTÉ noted.

In Australia, the Department of Foreign Affairs and Trade (DFAT) issued notices instructing that urgent sanctions enquiries be conducted by telephone due to the disruption. The outage prompted some observers to characterize the event as an "unscheduled long weekend" for organizations heavily reliant on Microsoft’s Exchange Online environment, The Register reported.

Engineers Struggle to Restore Service Stability Through Traffic Optimization

Microsoft engineers attempted to restore stability by scaling up virtual machines and redistributing traffic. However, the company reported that these actions did not result in sustained recovery. In some instances, virtual machines became stuck in a "bad state," preventing system updates from syncing as intended, according to The Register.

By Friday morning, Microsoft reported seeing "positive results for service stability and increased capacity" following new traffic optimization actions, the Irish Independent reported. Despite these efforts, the company cautioned that it was still pursuing multiple workstreams to address the underlying cause of the traffic influx.

Microsoft 365 Services Face Disruption from Technical Factors

The disruption primarily impacts Microsoft 365 services, including Outlook, Microsoft Teams, Copilot, SharePoint Online, and Microsoft Defender XDR. Services that do not rely on Exchange Online have generally remained functional, according to WIRED.

Microsoft has repeatedly stated it has no indication that malicious activity is responsible for the incident. The company is currently investigating technical factors, such as faulty software updates or infrastructure failures, as the primary cause, according to reports from The Register and the Irish Independent.

As the outage prevents reliable email transmission, organizations affected by the disruption have advised users to utilize alternative communication methods, such as telephone calls, for urgent matters. Microsoft has directed users to its official status pages for real-time updates on service restoration.

Earlier coverage: Microsoft Outage Disrupts Outlook, Teams, and Microsoft 365 Services Globally

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