For security resons not to allow php shells to be able to run on your server you must disable the shell_exec function in the php.ini using disable_functions

but when you do so on the time you want to autoinstall a cms with fantastico within your cpanel as a customer, you will be promted with so manny php errors that are caused because of disabling shell_exec

so how to have both the shell_exec disabled on the server and also be able to run fantastico delux?
there is an answer to that question
you must have a php sepreated for cpanel and have a seprated php.ini for cpanel php functions and php for your websites
in that way you can have both the php.ini containing shell_exec as a disabled function and also not to have any problem with fantastico as it is running on the cpalne with seprated php and php.ini that has shell_exec not disabled(it is enabled)
so to have your cpanel its own php, there is a predefiend scripts comming with cpanel that you can run to make the php jsut for cpanel
first run the following to update cpanel to latest version, making sure you have the lastest apckages available

then run the following to make seprated cpanel php:

please be pationt that it will take some times to complete according your server configration and setup.

so you are almost finisshed
the last step is to find out that you do not have shell_exec disabled in your cpanel php.ini
so check the following php.ini files

you are done
good luck

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2. creating backup of accounts in cpanel