Microsoft global outage hits Outlook, Teams and AI services: What went wrong?

Thousands of users faced a major Microsoft outage that disrupted Outlook, Teams and several Microsoft 365 services for more than five hours. The disruption also affected AI platforms such as OpenAI and Anthropic, which rely on Microsoft connectors, while businesses faced operational challenges. Microsoft attributed the problem to server availability and capacity issues, rather than a sudden surge in traffic. But what caused the outage, how many users were affected and why did it disrupt services beyond Microsoft's ecosystem? We explain.