In modern versions (v21.09+), the client software is generally free to install on any PC. However, advanced client features (like web-based admin or multi-monitor walls) may require separate add-ons. We will focus primarily on Server License Activation as it is the most complex.

You need a valid (https://www.exacq.com/). If you bought a license through a reseller, they should have registered the license key to your email.