Litespeed requires you to download the Trial key to try out their trial or use the WHM to do that. If you want to skip the process and fan of console, here is the easiest way to do this step by step:
$ cd /usr/local/lsws/conf
$ service lsws stop
$ mv trial.key trial.key_backup
$ wget --no-check-certificate https://license2.litespeedtech.com/reseller/trial.key
$ chown root:nobody trial.key
$ service lsws start
$ /usr/local/lsws/bin/lshttpd -t
[OK] Your trial license key will expire in 14 days!
Remember, this can only be done twice, the first month only. So you would definitely like to purchase the license and register it with the purchased key after your trial ends. Kudos!
You must upgrade to Litespeed “5.2.1 build 2 or later”, in order to upgrade to the next version of cPanel & WHM.
The error appears because Litespeed below 5.2.1 doesn’t have SSL compatibility with Cpanel 11.68. Although, this goes further, if you uninstall the plugin, and upcp will still fail to update the Cpanel/WHM. A workaround for this, is to install and uninstall the plugin through Litespeed auto installer. Here is how to do that:
Download Litespeed Auto Installer for Cpanel
# wget https://www.litespeedtech.com/packages/cpanel/lsws_whm_autoinstaller.sh
# chmod a+x lsws_whm_autoinstaller.sh
Install Litespeed for Cpanel/WHM using Auto Installer
# ./lsws_whm_autoinstaller.sh TRIAL 1 8080 username testpass1234 email@example.com 1 0
Uninstall Litespeed WHM Plugin
# /scripts/upcp --force