Enabling Safe_Mode

First, Connect to your Server via SSH using Putty or Similliar, or Under Gnu/Linux type in a terminal:

ssh root@ip-address -p port

You'll have to edit php.ini file, Type: nano /etc/php.ini

if you don't know the location of your php.ini file, Create a php file (phpinfo.php) With this content:

Upload it to your Website/Server and open it in your browser, You'll find the location of php.ini in "Loaded Configuration File"

Find (Ctrl + W):
safe_mode = Off

Change it to:
safe_mode = On

Disabling Functions

Find (Ctrl+W):

disable_functions =

Then add the functions that you want to disable, seperated by comma.

Example:

disable_functions = dl,popen,system,exec,shell_exec,suExec,passthru,escapeshellcmd,escapeshellarg,symlink