In joomla you can change the password from back-end normally. For this you need to login to your back-end and go to Users -> User Manager. A list of users appear. Click the name of the admin and an edit form will appear. Now from here you can change the password of admin.

But in some case that might happen to you that you have forgotten your password, or your password has been hacked or someone has changed your password. Then you might be not able to login to your administrator. To recover the password there are various methods available in Joomla.

Method 1: configuration.php file

If you can access Joomla installation configuration.php file from your server, then you can recover your admin password by following the steps given below:

• Connect to your site from FTP. Find the configuration.php file.

• Now you can add following lines to the bottom of the configuration.php file:

  public $root_user='validexistingusername';

  Replace the 'validexistingusername' with any user that is registered to the site with Author rights or higher. Now this user is a temporary admin of the site.

• This user now able to login in the back-end of Joomla site and can edit/add users by selecting(after login to the back-end of Joomla site) User Manager -> Users. A list of users appear. Click the name of the admin and an edit form will appear. Now from here you can change the password of admin.
• After following the above steps remove the line you have added to the configuration.php file either by clicking to the link "Click here to try to do it automatically" given at the top after you login the the backend. It will automatically remove the line or you can do it manually by editing the file.

Method 2: Editing the database

• Change the password in the database

If you have the credentials of database then you can directly change the password of the admin by accessing the database. For this first of all, login to your phpmyadmin and select the database of the Joomla site in the left hand side. This will display all the tables of the Joomla site. Simply go to the _users(with some prefix that you have set while installing the joomla) table. Search for the user whose password you want to change,select it and press the edit icon. A form will appear that allow you to change the password. Add the following line to the password field:

c56465fab9aa665834ca6b7445ffffa2:7NJsf069XzgTuoxXA1N4NBzjtbZvrL8C

It will set your password "admin". Now you can login to your Joomla administration system using your admin username and password as "admin". Change the password of the admin for security reasons.

• Add a new Super User(Admin of Joomla)

Open phpmyadmin and select the database for your Joomla site in the left hand side. All the tables will be displayed. Now press the SQL button at the top of the phpmyadmin page. This will display the page with field to run sql queries. Copy and paste the following query:

INSERT INTO `jos_users`   (`name`, `username`, `password`, `params`)
VALUES ('Administrator2', 'admin2', 'c56465fab9aa665834ca6b7445ffffa2:7NJsf069XzgTuoxXA1N4NBzjtbZvrL8C', '');
INSERT INTO `jos_user_usergroup_map` (`user_id`,`group_id`) VALUES (LAST_INSERT_ID(),'8');

Change the prefix of the tables 'yourtableprefix_users', 'yourtableprefix_user_usergroup_map' and press go. Now you can access the back-end of your site with username admin2 and password admin. Change your password once you logged in.