From the joomla docs How do you recover or reset your admin password?
Method 1: Configuration.php
Use an FTP program to access your site's ftp
Locate and download the configuration.php
Using a text editor open configuration.php and add the following line. Substitute myname to a name of an account with administrator access that you know the password.
Joomla uses the Xyz8_users table for storing user data.
Reseting the passwort is simple just execute this query in phpmyadmin:
update Xyz8_users set password=md5('newpassword') where username='yourusername';
After changing the password with SQL, log into Joomla and it will be converted to an update passwort hashing method.
In phpMyAdmin, go to the Xyz8_users table (change the table prefix, Xyz8_ to your table prefix if it is different.)
Select the record for the Super User account (the Super Admin account has an ID of 62 or 42 by default).
Copy and paste a known MD5 hash (one of the longer character strings below) into the password field.
admin = ...
you should look for table Xyz8_users.
2 List with all users will appear. Find the user you want to edit and click the "Edit" link in front of the row
Find the "password" row and click on the select box under the "Function" column.
Select "MD5" and type the new password in "Value" textarea.
Click the "Go" button at the bottom of the page and ...
There's also a tool available for Joomla 2.5 (haven't tested with Joomla 3): http://myext.eu/en/j25-login
It's simply a PHP file that you upload to your /administrator/ folder and visit in your browser.
Log in as Super admin without account
How to: Сopy the file in "administrator" and go to [your_site]/administrator/log.php
WARNING: remove the file ...
Unfortunately, this can only be done using a core modification. Open the file administrator/components/com_users/views/users/tmpl/default.php and, just above the line
$canEdit = false;
Add the following line:
This will prevent super users from being displayed to anyone who is a non super user.
In fact, Setting 2 would only make sense to me if you..
...Have no inheritance of permissions to the top
...Only one usergroup has access to a specific task
Then it makes sense, if the superuser should simply have all tasks / views / options of the custom 1/2 groups this can be solved by inheritance in a cleaner way.
Edit: indeed superuser has no inherited ...
User Group is for grouping users. Viewing Access level is to define what a User Group can access.
So, everytime you create a new User Group you need to link that new group to an Viewing Access Level.
Oppositely, when you create a new Viewing Access Level, you need to assign a User Group to that new Viewing Access Level, so then any item created with that ...
Imho the only way would be to delete the session in the database (#__session table).
Then the user is forced to log in again and the permissions are calculated fresh.
UPDATE: As the comment below, there is no "joomla way" to destroy the session if we are using JSessionStorageNone. So, you likely have to wait till that users session times out or he logs out ...
It is possible for recover the admin password.
Two ways to recover the admin password.
Edit configuration.php file
Edit #__user table in database.
1.Navigate to phpMyAdmin and select the database for the Joomla! site in the left-hand ...