On a Linux web-hosting account, you can selectively enable or disable various PHP extension libraries to enable additional PHP functions. For example, if you are accessing a MySQL database using PHP, you will need to install the mysql PHP extension library beforehand.

You can manage your installed PHP extension libraries in HostPilot in the 'Web/FTP Server > Apache Server > Add-Ons > PHP > Configuration' section. The page should look like the image below:

PHP libraries

Please note that after enabling or disabling PHP modules it is necessary to restart your Apache service using the 'Web/FTP Server > Apache Server > Start/Stop' HostPilot page.