Reset Password root Ubuntu

So First Step is Boot in to Recovery Mode:

You will see the following screen. Now select "root - Drop to root shell prompt" and press "Ok"

Here is video tutorial

If you forgot your username enter this command to know:

Terminal Command:
ls /home

In linux case is sensitive about username and password, If you have upper case than you need to enter same letters.
Mount root with following command:

Terminal Command:
mount -rw -o remount /

Now Enter following command to reset your password:

Terminal Command:
passwd username

For example (See the picture above):

Terminal Command:
passwd noobslab

Now enter your new password and confirm it.
Reboot pc:

Terminal Command:
exit

That's it.

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