warning: shell_exec() has been disabled for security reasons

If you get an error like this, it means that shell_exec is disabled in the php.ini file.  To re-enable it, you need to do the followng

1. SSH to the server
2. edit the php.ini file (on cpanel it’s /usr/local/lib/php.ini)
3. search for the line that says “disable_functions”
4. remove shell_exec from this line
5. Save the file, and restart apache.

If you do not have root access to the server, then you’ll need to ask your hosting provider to do this for you.