Thank you for your message.
The Viewer module works in trial mode for 30 days. In order to use the program beyond the 30-day trial period, you must register the Viewer with a valid license key. To obtain a free license key please refer to this free license key generator
. The license key will be sent to your email address.
To register the Viewer with the free license key, please, follow this tutorial
. Other program modules such as Host, Agent, and RU Server do not require registration.
Hope that helps.