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After I entered this command in terminal:

sudo sh -c 'echo "greeter-show-manual-login=true" >> /etc/lightdm/lightdm.conf'

and I reboot my PC I cannot login. After I select the os in GRUB it takes me to a black screen and I can't do anything even though Ubuntu seems to run; everytime I turn off my computer via the power button the Ubuntu logo appear. I think it has got to do with lightdm. I have tried to run in safe graphics mode but nothing happen what should I do?

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up vote 1 down vote accepted

I hope this will help you

When you power on the computer, and ubuntu will load, try to press [Left Control] + [Left Alt] + [F1] Then log in to the system via terminal, then go to the path /etc/lightgdm by command:

cd /etc/lightdm/

Then edit the file lightdm.conf with your editor like: nano or vi (nano is much more easier here). It will ask you for your password again

sudo nano lightdm.conf

And delete the whole line that you added


Then save it with keyboard command [Left Control] + [x], it will ask you "Save modified buffer" press key [y] and then it will ask "File Name to Write: lightdm.conf" just press [Enter]

Finally type

sudo reboot
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Or use live cd, and then edit the file. – xylo May 11 '14 at 14:01
it worked so thank you very much but if i want to have a root acount and lightdm is causing me these problems how can i have a root account – Zorbacator May 11 '14 at 14:35
In ubuntu 14.04 they moved and renamed that file. Go to "/usr/share/lightdm/lightdm.conf.d" and there is a file named "50-ubuntu.conf" just add that line "greeter-show-manual-login=true" at the bottom of that file, and reboot system. – xylo May 11 '14 at 14:51
@xylo Uhhh..isn't that my answer below? – VenkiPhy6 May 11 '14 at 14:52
I'm on my android, your answer did not load so i did not read it. Sorry mate :) – xylo May 11 '14 at 14:55

As far as I know, /etc/lightdm/lightdm.conf doesn't exist in Ubuntu 14.04 ! I tried

locate /etc/lightdm/lightdm.conf 

in my Ubuntu 14.04 and this is what I got :-


Therefore it is clear that /etc/lightdm/lightdm.conf doesn't exist. Well, I must add that it is not present there. Instead use /usr/share/lightdm/lightdm.conf.d/50-ubuntu.conf . Its content is same as that of /etc/lightdm/lightdm.conf as shown below:-


So remember:-

The equivalent of /etc/lighdm/lightdm.conf in Ubuntu 14.04 is /usr/share/lightdm/lightdm.conf.d/50-ubuntu.conf .

Therefore you might edit your above command to :-

sudo sh -c 'echo "greeter-show-manual-login=true" >> /usr/share/lightdm/lightdm.conf.d/50-ubuntu.conf'

and it might work!

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thank you very much it worked – Zorbacator May 11 '14 at 14:56

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