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i'm having a serious problem. i use dual os so i'm posting with windows. i am having a problem. somewhat about 2-3 hours before everything was working fine i have modified Ubuntu a lot and was using mac os X login screen. it was working fine . but i was just having fun and typed this command in terminal to power off (using Ubuntu 13.10) {and using root}.

sudo shutdown -h now

also I changed password for su using

sudo passwd root

I kept my laptop aside and came after 2-3 hours. it booted with a splash screen of mac. then it took to a blank screen (OK this happens every time, but after 5-10 seconds login appears), but these times I'm getting a black screen with a mouse. I can move mouse but can't login. only black screen is there, but everything else is working when i press powerbutton it shuts down like usual. screen somewhat looks like this: screen

I'm stuck, please help me!


I got an answer if this happens to anyone else. Just follow the steps:

  1. Open terminal using Ctrl+Alt+F1

  2. Login to your account.

  3. Type 'startx'

(If this does not work, try 'sudo startx')

  1. Your desktop will appear after some time. Do what you want to do.

  2. In my case I had changed my login greeter, so I edited my lightdm.conf and used the default greeter.

share|improve this question
what happens when you try to access the virtual shells (Ctrl+Alt+F1, Ctrl+Alt+F2 etc.) – tr33hous Mar 26 '14 at 13:47
it said pcname login:dont know what to type and password : in next line – Ashwin Sekhari Mar 26 '14 at 13:49
up vote 3 down vote accepted

To fix this, follow the steps below:

1- Turn on your computer and wait for it too boot up.

2- Once it boots up, press Ctrl+Alt+F1 to enter terminal

3- Type your username, press enter, and type your password and press enter again.

4- Now type


This should start your desktop. Once here, you can uninstall/reset whatever was causing the problem (in this case Mac OS LightDM theme).

5- Reboot the computer it should boot up normally!

share|improve this answer
but i dont know my user name altough i know my acc name .is my user name that one which come sin terminal ****@pcname : – Ashwin Sekhari Mar 26 '14 at 13:50
Try logging into root. Un:root. PW:(what you set it as). Then type 'CD /home' then type 'ls'. What does that output? – That Coder Guy Mar 26 '14 at 13:51
im using this login – Ashwin Sekhari Mar 26 '14 at 13:52
Sorry.. Your username is what you said in the first comment – That Coder Guy Mar 26 '14 at 13:53
ok let me try rebooting my pc so will take some time to post btw what to type here Un:root. PW:(what you set it as !!!here!!) – Ashwin Sekhari Mar 26 '14 at 13:54

Try to run the following command:

sudo apt-get install lightdm --reinstall

and restart, if it works then enjoy.

If it does not work, then you can run following command:

sudo deborphan | sudo xargs apt-get -y remove lightdm --purge && sudo apt-get install lightdm
share|improve this answer
thx for help but i resolved – Ashwin Sekhari Mar 26 '14 at 14:31

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