KMS Activator is a software tool used to activate Microsoft products, including Windows and Office, by simulating a Key Management Service (KMS) server. Bypasses Microsoft activation using KMS protocol. Activates products without needing an online connection. Activation expires after 180 days, requiring renewal. Risk of violating Microsoft’s terms of service with KMS activation. Long-term use may cause technical issues or security vulnerabilities. Can be used on various editions of Office and Windows.