There are several alternatives to KMS for activating Windows. One popular method is using a retail product key, which can be purchased directly from Microsoft or authorized retailers. Another option is the Digital License (formerly known as Digital Entitlement), which allows users to activate Windows based on their Microsoft account and hardware configuration. Additionally, Microsoft offers volume activation methods like MAK (Multiple Activation Key) for organizations that do not wish to use KMS. Each method has its pros and cons, depending on the user’s specific needs and environment.