You can purchase a license directly from the official Radmin website or from an authorized reseller. The licensing model for Radmin Server is as follows: each Radmin Server installation you wish to control requires its own license key. These are perpetual licenses, meaning you pay a one-time fee to own the software version you purchased indefinitely. Support and optional upgrade subscriptions may be available separately.
If you have previously purchased a license and lost it, you can request your license key again via the Radmin Helpdesk key request form . Activating Radmin Server 3.5.2
The requested "radmin server 3.5.2 license key new" typically refers to attempts to find unauthorized activation codes for Radmin Server, a high-performance remote control software.