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I was trying to tweak Ubuntu after fresh installation and following various links on web stating "Things to do after installing Ubuntu 14.04"

I was trying to remove Guest User Account from the start screen and was following some text in the command prompt. I can recall only few :

  1. sudo
  2. gedit /lightdm/lightdm.conf

and to add below line at the end of already written lines (But it was blank, still I added and saved it). (In the document (looked like Advance notepad :P) which just opened using above piece of code)

3 . greeter remote-login=false

and then reboot.

But here comes the problem. Machine is booting up normally, Ubuntu on purple is coming.... Dots below Ubuntu ticking.... and then black screen.....

I guess I've deleted both accounts (Mine & Guest)? Now it has no entry to let me in. Is there any option to fix it or to get access via a new user account?

I do have a Live USB with me. Can it help ?

Update: I tried to boot in Root prompt while holding shift (when Ubuntu was booting) and try to edit sudo nano /etc/lightdm/lightdm.conf it was showing only one line it i.e. greeter-show-remote-login=false When I try to edit & save it with [SeatDefaults] it was showing no write permission.

share|improve this question
Sorry I don't know what happened in this case. The file /lightdm/lightdm.conf shouldn't have been blank. A black screen at boot is usually means problems with graphics driver. – user68186 Aug 4 '14 at 18:34
At this point you may be better off if you do a complete reinstall and start from scratch. – user68186 Aug 4 '14 at 18:39
I've searched on and found it should be like : [SeatDefaults] user-session=ubuntu greeter-session=unity-greeter allow-guest=false problem is how can I edit this file while in root command prompt, it's not letting me to edit it, just read permission. Thanks – Gaurav Aug 4 '14 at 18:41
Just boot as normal, you can switch to another vty when it stops. – squarebear Aug 4 '14 at 18:48
up vote 3 down vote accepted

Okay sounds like maybe you have some error with your /etc/lightdm/lightdm.conf

Boot your computer and when it stops and hit Ctrl+Alt+f2

You should get a login prompt. Login with your regular username and password.

Now to fix the config

sudo vim /etc/lightdm/lightdm.conf


sudo nano /etc/lightdm/lightdm.conf # if your not comftable with vim, nano is easier.

Edit your config so it looks like this:


Your not going to have the luxury of copy and paste so be careful to enter it correctly make sure there is nothing else in the file but this. Save the file and then type

sudo reboot

It should then boot normally.

share|improve this answer
Unless one is already familiar with vim, I vote for nano. It is installed by default and I find it much easier than vim. – user68186 Aug 4 '14 at 18:45
@user68186 True for new users, If I use nano now I end up with :wq scattered throughout my files! – squarebear Aug 4 '14 at 18:49
Guys, You're Awesome :) It's working now.... THank you so much. I'm really liking ubuntu and specially it support. Thanks a ton. – Gaurav Aug 4 '14 at 18:50
@Gaurav Cool, Glad its working for you. – squarebear Aug 4 '14 at 18:51

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