Authentication token manipulation error
I installed Ubuntu Server using Oracle VM on my Windows 7 for practicing GNU commands.
I used the
passwd tool but after using the command I am not able to login into my Ubuntu.
When I type my password nothing happens. Nothing gets written on the black screen. And when I press Enter it says
_login incorrect_ And one more thing is says
_hint: num lock on_
When I tried to change the password into recovery mode it says:
_Authentication token manipulation error_
I reinstalled my virtual machine but the problem persist.