Overview
- The outage began on 12 November 2026 when Microsoft logged incident EX1550543 and users worldwide reported widespread failures accessing Exchange Online and Outlook.
- Microsoft says many servers failed automated health checks and became unavailable, and the company reports no evidence the disruption was caused by a cyber‑attack.
- Engineers have restarted affected servers, paused some updates, switched to alternate health checks and are rerouting user traffic region by region to restore service.
- The failure produced large complaint spikes on monitoring sites and disrupted banks, airlines and government agencies, with Australia activating a priority recovery arrangement for ASIO and the AFP.
- Services are partially restored in regions such as Asia‑Pacific but Microsoft’s status pages still show degradation and the company is processing large email backlogs while preparing a detailed post‑incident report.