• Right click on files/folders -> Properties

• Open terminal and type the following

                  sudo -K

• Automatic login is not secure and we don't recommend it. 

• Here is what you should do.

• Goto

System -> Administration -> Login Window-->Preferences
Security -> Allow local system administrator login (Checked)

• Open terminal and type the following 

             sudo passwd -l root

• Restart Ubuntu in safe mode.  

• Open terminal and type the following

                           passwd

•  change root password.

• John is a active password cracking tool.To install it Goto application-->accessories-->terminal and type the following.

               sudo apt-get install john

• Then type the following

                                    sudo john /etc/shadow
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• Their is an application called users and groups in ubuntu which have a really simple and easy to use interface.With this application you could  add/delete/manage groups with relative ease.
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•  Their is an application called users and groups in ubuntu which have a really simple and easy to use interface.With this application you could  add/delete/manage groups with relative ease.

• Goto system > administration > Users and Groups from your Ubuntu. 

Add/delete/manage users using Command line in Ubuntu
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