Passwd command can allow us to change user password, however, we often may find Authentication token manipulation error when changing, which cause us not to change new password for user. In this tutorial, we will introduce how to fix this error and update new password for user.
Use mount command
Enter code below in root prompt.
mount -o rw,remount /
Use passwd command to change new password.
If your username is zhilun. You can do like this:
then you will enter new password.
Finally, reboot your ubuntu system.