PHP warning : Module 'mcrypt' already loaded

Question

When I run a command with PHP, it shows me an error. E.g when I run php -v to see my PHP-version it shows me an error then the informations about PHP:

Module 'mcrypt' already loaded in Unknown on line 0

zied@ubuntu:~$ php -v

PHP Warning:  Module 'mcrypt' already loaded in Unknown on line 0

PHP 5.4.25-1+sury.org~quantal+2 (cli) (built: Feb 12 2014 11:11:30) 
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2014 Zend Technologies

Answer 1

Your php.ini contains two or more of these lines:

extension=mcrypt.so

Remove all except one.

php.ini usually lives in /etc/php.ini or /etc/php5/php.ini. Sometimes additional .ini files are included, you can see all of them with:

$ php -i | grep .ini\$
Loaded Configuration File => /usr/local/etc/php.ini
Additional .ini files parsed => /usr/local/etc/php/extensions.ini
user_ini.filename => .user.ini => .user.ini