Cannot login after enabling "don't ask for password on login"

[Ruki]

HELP!

Since I checked off the option “don’t ask for password on login”, I only see the “log in” button when startting but nothing happens when I click on it. Only the screen blinks once but it doesn’t log in anymore.

What can I do to get my user account working again?
It is the only account on the computer and I need it urgently

I use the MATE Desktop Environment 1.12.1
Ubuntu Release 16.04.1 LTS (Xenial Xerus) 64-bit
Kernel Linux 4.4.0-42-generic x86_64

Thanks for any ideas

[ouroumov]

Try this:
Power on the PC, hold SHIFT till you see the GRUB menu.
Go to "Other Options for Ubuntu" or equivalent.
Boot last kernel in recovery mode.
Select 'root' to perform admin tasks.
Once in the root shell, issue the command:

mount -o remount,rw /

Then use the command:

passwd you

(Where 'you' is your user name on the machine)
You'll be asked twice for the new password, and won't see stars echoed back to you as you type - this is normal.

Then reboot using:

init 6

Edit: advising this because of this comment from @lah7

Turn Login screen back on

Possibly a tad bit unnecessary, I’ve found that a new password needs to be set when toggling the “Don’t ask for password at login”.

Edit: also see this:

Disable auto login

Open a terminal. sudo nano /etc/lightdm/lightdm.conf It displays some text as follows: [SeatDefaults] greeter-session=lightdm-gtk-greeter user-session=mate autologin-user=username Solution This would be your particular user name that is automatically logged in with or without password. Delete this username and type in the administrative username or leave it blank. Shut down the system. It will go back to the login selection screen. Just power down the system and put it on again.

[Ruki]

Thank you, I tried:

@ouroumov

Power on the PC, hold SHIFT till you see the GRUB menu.
Go to "Other Options for Ubuntu" or equivalent.
Boot last kernel in recovery mode.
Select 'root' to perform admin tasks.
Once in the root shell, issue the command:

mount -o remount,rw /

Then use the command:

passwd you

(Where 'you' is your user name on the machine)
You'll be asked twice for the new password, and won't see stars echoed back to you as you type - this is normal.

Then reboot using:

init 6

I still have no option to Log In with or without a password.
Other suggestions?

[ouroumov]

Try @Wimpy's suggestion to edit lightdm.conf in the linked post above.
You can avoid booting into recovery by switching to tty1 using CTRL+ALT+F1 (switch back to graphics using CTRL+ALT+F7 when you're done) and login from there.

Edit: alternatively if all you care about is getting access to your files:

Create a new user from root shell using:

adduser newusername

After that you can make that user an admin using:

adduser newusername sudo

Use root shell to copy files from your old user to the new:

cp -rv /home/you/* /home/newusername

Then change file ownership to your new user

chown -R newusername:newusername /home/newusername/

Then reboot, with some luck you'll have option for that newuser in lightdm login screen

[Ruki]

ok, using CTRL+ALT+F1 I can somehow type in my username and password which seemed quite a relieve first.

However, When switching back with CTRL+ALT+F7 I am still seeing the log in button.

And when typing

@ouroumov

sudo nano /etc/lightdm/lightdm.conf

I see an empty screen and NOT

@ouroumov

some text as follows: [SeatDefaults] greeter-session=lightdm-gtk-greeter user-session=mate autologin-user=username

Is it possible to log in after using CTRL+ALT+F1 and after entering my user name and password? Is there any command logging me in?

[terzag]

You can try to put this in lightdm.conf:

[SeatDefaults]
autologin-user=

(Leave autologin-user empty, don’t put your username.)

It should ask your password again and hopefully let you access the session.

[Ruki]

I just found a solution elsewhere.

It went as follows:
Press CTRL+ALT+F1 and log in there and run:
sudo chown -R $USER:$USER $HOME
Then press CTRL+ALT+F7 and try to log in

No Idea what it did, but now I am in!
Thanks for your precious time!

[malwaredpc]

It changes the permissions of the home directory to the current user and group of your session. In the end, it was a matter of permissions.

[ouroumov]

Might be related to this:

Login Manager issue

I’m having an issue with the login screen (LightDM?) I am hoping someone can help me with. I setup my home PC so that my account does not require using the password to log into my profile. Less secure, I know, but for home use, it seem to be of little issue. Well, as of this morning I ran into an issue when I needed to reboot my computer and now with my profile selected I hit ‘login’ and nothing happens, it doesn’t login. I get an instant blank black screen, almost like a refresh, and I am back…

It'd be nice if we had a clear path to reproduce. :/