Reconfiguring Lightdm can fix your problem
- Press CTRL+ALT+F1 when blank screen appears.
tty1 CLI appears then login with your user name and execute following commands
sudo dpkg-reconfigure lightdm
lightdm from the list, and restart your system:
sudo reboot now
If this doesn't work then you have to follow following methods.
Installing GDM (a display manager like lightdm) can fix your problem:
- This method works when you are able to go to at least the
command line interface.
Press CTRL+ALT+F1 or CTRL+ALT+F2 when your system starts and starts freezing or black screen appears. It will let you to use Command Line Interface. Then login using your username and password, and try following commands:
$ sudo apt-get install gdm
$ sudo dpkg-reconfigure gdm
then selected gdm from the list, and restarted your system:
$ sudo reboot
Your system will be restarted with a login screen which will let you to access your system.
Method 2: If 1st didn't work for you then you can try this method. But it would be very long for you:
Here are the steps how to install using 2nd method
Go to following link and download gdm for Ubuntu 12.04.2 amd64. (chose
proposed universe out of three listed there.)
Put the *.deb file just installed to any pendrive.
Then login in save mode or
Recovery Mode. After a lot of text displayed in black
screen one window will come which list some options. First go to option Grub, it
will mount your file system in read/write mode. Then chose root option in order
to login as root. Then go to the pendrive where you saved the deb file. The drive
should be listed in in /media. I am assuming that you saved the file in
pendrive is the name of your pendrive)
# cd /media && ls
(which will list your
pendrive if you don't get
folder then go to Mount Pendrive Section at last, then come back here and continue to next step.)
# cd /media/pendrive/gdm
(go to gdm directory where .deb file is saved.)
# dpkg -i *.deb
While installing gdm one window will come which will ask your to chose lightdm or gdm
from the list. Chose gdm. If this window doesn't appear then try following command:
# dpkg-reconfigure lightdm
(chose gdm) Then finally execute following command:
# reboot (reboot your system)
Mount Pendrive Section
- Mounting pendrive while working in recovery mode.
Run this command:
# fdisk -l
Find your device in the list, it is probably something like
/dev/sdb1. Then execute other commands one by another:
# mkdir /media/pendrive
Run this command if your pendrive is formatted in FAT/FAT32.
# mount -t vfat /dev/sdb1 /media/pendrive -o uid=1000,gid=1000,utf8,dmask=027,fmask=137
Or this command if your pendrive is formatted in NTFS
# mount -t ntfs-3g /dev/sdb1 /media/pendrive
Hope it will work for you.. For any further assistance please reply..