Before downloading the SafeSquid installer(s), you MUST register to create your account on SafeSquid's self-service portal at - https://key.safesquid.com/. Registration is free, and requires just a few minutes. Your registered account also provides the management of SafeSquid's cloud-backed features, like Custom Web Categorization, VPN support, Configuration Backup, Subscription management, etc.
All registered users are provided with a Product Activation Key. After the SafeSquid installation, you must upload this activation key via SafeSquid's Browser based Interface. Your users may not be able to access the web until then. Use the same Activation Key across all your instances of SafeSquid, to ensure easy replication of policies, and other common aspects.