If you want to create a new root password then try to login through single-user mode.
- To get enter into your single user mode first reboot your system. If you are using GRAB as default boot loader then use details given below.
- First highlight the installation which you want to edit in your boot loader menu, then type [A] to get enter into your append mode.
- Now you enter into a prompt with the similar code given below.
- After that click space bar key to add blank space and then add the word “single”.You have to do this to tell “GRUB” about "boot single-user Linux mode". After that, you found following details given below.
- After that click enter button and “GRUB” will automatically boot the single-user Linux mode.when you completed this step then you get following code
- Now you can change the password by typing
It will ask you to reset the password for verification. once you do that your password will be automatically changed. then reboot the computer and try to log in again.