Microsoft Defender for Endpoint has evolved from a basic Windows antivirus into a comprehensive enterprise security platform. Our 2026 review evaluated across an enterprise environment of 1,000+ endpoints. Defender achieved 99.7% block rate including 100% of our ransomware samples. The advanced hunting feature allows KQL queries across all endpoint telemetry. In simulated attacks, Defender consistently detected our activities within minutes with clear attack timeline visualizations. The threat and vulnerability management module identified 234 vulnerabilities prioritized by exploitability. For organizations with Microsoft 365 E5, Defender for Endpoint is included at no additional cost.