Ubuntu forgot user Password resolution--authentication token manipulation error

1. Restart the system, and hold down the SHIFT key to enter the Grub menu;

2. Select the recovery mode recovery model;

3. In recovery menu, select root drop to root shell prompt;

4. Enter the passwd user name in the command line;

If the successful appears to indicate the success of the modification;

If it appears:

Describes no permission changes.

Workaround at this time:

Re-mount the root/read-write mode, enter Mount-o rw,remount/

Change the password again to succeed.

About Mount-o Rw,remount/

It is important to note that the mount point must be a directory that already exists, and this directory may not be empty. The files used in this directory are generally RO permissions and need to be temporarily changed to modifiable permissions.

Parameters:

-O < options > Specifies options for mounting the file system, some of which can also be written to/etc/fstab. Commonly used are:
Defaults Use default values for all options (auto, Nouser, RW, suid)
Auto/noauto Allow/disallow installation with the –A option
Dev/nodev/Do not interpret special devices on file systems
Exec/noexec Allow/Disallow binary code execution
Suid/nosuid Confirm/Not confirm suid and Sgid bit
User/nouser Allow/Disallow normal users to mount
CODEPAGE=XXX code page
Iocharset=xxx Character Set
RO mount in read-only mode
RW mount in read-write mode
Remount Reinstall a file system that has already been installed
Loop mount "cyclotron device" and "ISO image file"

Ubuntu forgot user Password resolution--authentication token manipulation error