The trial version of Serial Port Redirector CE has some limitations such as a time trial. Once you have purchased the license, a license key will be sent to you to unlock the software for full use.
1) Create empty text file license.key.
2) Select text block of the license code (including --BEGIN and --END lines) and paste it to the file.
3) Save the file to the folder where Serial Port Redirector CE is installed.
4) Soft-reset the device to apply the license key.