PHP Warning: show_source() has been disabled for security reasons
PHP Warning: show_source() has been disabled for security reasons
Some of the web hosting providers disable this PHP function server-wide for security reasons.

show_source has been disabled for security reasons
Follow the below steps to fix the error by enabling show_source function.
1. Open a new terminal and log into your server via SSH as ‘root’ user
2. Check whether show_source is added in PHP disable functions
Run the below command to check whether show_source function is added in PHP disable_functions.
disable_functions = show_source
On my server php configuration file is in path /etc/php.ini. The path might be different on your server. Run the command “php --ini” to find the path of the php.ini file.
The above command output shows show_source PHP function is added in disable_functions.
3. Remove show_source from disable_functions
open php.ini file using your favorite editor.
Go to disable_functions line and remove show_source.
Save the PHP configuration file and exit the editor.
This will enable the show_source PHP function.
Note : This function might be disabled to harden the PHP installation. You must enable this function only if it is required. Functions added in PHP disable_functions are exploitable dangerous PHP functions.
4. Restart the web server
You must restart the web server for changes to take effect.
5. Create a phpinfo file to verify
Create a phpinfo file under your website to check whether the show_source function is removed from the disable_functions line.

phpinfo show_source is disabled
In the above phpinfo, you can see that show_source function is disabled.