Microsoft rules out cyberattack and AI as cause of global Outlook and Teams outage

Microsoft experienced a global outage on Thursday, November 12, that disabled access to key services like Outlook, Teams, Copilot, and SharePoint for businesses, government agencies, and educational institutions worldwide. The disruption originated in the United States and persisted into Friday, with users unable to send or receive emails or utilize other cloud-based workplace solutions.

Microsoft's technical team identified issues with server availability and an overloaded process on affected servers as the root causes. They were actively working to restore the infrastructure, but the problem persisted, with some servers returning to service while demand shifted to the remaining operational infrastructure. The outage impacted not only Microsoft 365 services but also external systems relying on Microsoft connectors, including those used by OpenAI and Anthropic.

IndiGo, Akasa Air, and several financial firms in Taiwan were among the organizations reporting service disruptions due to email support and fund management platforms relying on affected Microsoft services. Microsoft initially blamed the issue on heightened infrastructure loads but clarified it was caused by a significant number of servers unexpectedly going offline, disrupting the balance of demand.

Despite attempts to redirect traffic through alternative pathways, Microsoft recognized that these measures had not led to a full recovery. The company is now considering additional steps to enhance infrastructure stability. Microsoft has not found any evidence of malicious activity behind the outage, and Australian Home Affairs and Cyber Security Minister Tony Burke stated they do not believe it was a cyberattack.

This latest disruption follows similar widespread outages in recent years, underscoring the critical role of major technology infrastructure providers in global operations. In November 2025, a major Cloudflare outage affected millions of websites globally, highlighting the vulnerability of businesses and online platforms to disruptions from a few key providers.