WHMCS System System Tutorials In some circumstances, you must force WHMCS to perform a license update. When you move your WHMCS installation from one server to another, you may need to perform additional steps like updating your license. When you move your WHMCS installation from one subdomain to another on the same server, you may need to perform additional steps like updating your license. You can take steps to optimize performance on larger installations. You can use cPanel's MultiPHP Manager and MultiPHP INI Editor features to upgrade PHP. To ensure that your WHMCS installation can function, your system URL setting must be correct at all times.