Ubuntu is not starting on my compaq computer

[Aileen_L]

After installation of Ubuntu operating system,I am unable to login after finishing the installation, I got black screen and nothing happen to be continued ? I needed to restart the computer and after I got login screen, and everything went blank. I got a fatal error message like /tmp/.X0-lock, So I tried to do with some earlier suggestions : ls /tmp/.X0-lock and rm /tmp/.X0-lock but it replied me "cannot remove '/tmp/.X0-lock' : operation not permitted", would you help ?

[Solomon]

If your system goes to black screen After installation of Ubuntu so you need to press the "CTRL+ALT+F1" try to do this,If it will be successful then no issue about anything it will ask you about "Username and Password" and go fine,If it is not going well your graphics card throwing this error and you need to check your xorg.conf file which is kept into this location /etc/X11/xorg.conf.

[MrChris-]

In case of your fatal error message "/tmp/.X0-lock", Don't try to remove it first go and just execute this file using this command
sudo rm /tmp/.X0-lock
The cause of this error is that your "X-server" is already runnung.

NOTE: At the time of startup of choose " Ubuntu recovery mode " option from GRUB and type startx

[Calvin K]

Configuring Xorg.conf:

Start your computer in recovery mode to select it from GRUB just wait for loading the operating system and
type this command on the terminal
dpkg --configure -a
Then reconfigure the X-server using this command
dpkg-reconfigure xserver-xorg
and type this command
sudo vi /etc/X11/xorg.conf

Before entering this you should know the password of Root user and edit this detail into file.Make a search for your monitor's full space you can use google to do that and add the horizontal sync rate and the vertical refresh rate at the end of the monitor section.