What to know about Microsoft's outage and why it takes so long to restore email services
Unlike modern web apps or authentication gatekeepers, email wasn't designed to fail fast, meaning to immediately halt when a problem arises.
The recent Microsoft 365 outage that began on November 12, 2026, extended beyond email services, impacting popular tools like Microsoft Teams and the AI assistant Copilot. While Microsoft reported ongoing improvements in service availability, users continued to encounter intermittent access issues or delayed email delivery as of November 13.
Email remains a vital tool for organizations, with password resets, invoices, legal notices, and cybersecurity incident response all depending on it. Unlike many other cloud services, email's decentralized store-and-forward architecture means it isn't designed to fail quickly, unlike typical web apps or authentication gatekeepers.
When a cloud service breaks, users are immediately locked out with an error message, preventing further access. However, email's architecture allows messages to be sent even when the destination is unreachable, resulting in millions of messages piling up in queues across the internet when a major provider like Microsoft goes down.
The architecture of email explains why outages feel drawn out and why failures can impact entire sectors – the massive backlog of messages and retry attempts from every other mail server on the internet must be processed before traffic returns to normal speed.
Written by urgent.news from PBS NewsHour's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
