Linux server's can be accessed through GUI(Graphical User Interface) or CLI(Command Line Interface).
Some times User will face some issues when accessing GUI such as
- Blurred screen.
- System crashes when users try to access GUI.
- Only particular user will face an issue not able to access GUI.
- Resolution problems.
ISSUE1: If it is for a single user this GUI related problems will occur due to some space issue
So check these following things
- Check weather his disk quota is exceeded or not(when ever GUI is started in Linux/Nix it require some temporary space which is used to store some temp files for the purpose of GUI running), so if there is no free space left for the user GUI will not start for that particular user.
- Remove temporary files which are not in use for that particular user.
ISSUE2: If the GUI is not working for all the users then there is some configuration issues in xorg.conf file.
The best and simple way to resolve this issue is just take a backup of the existing file and regenerate the new config file
#mv /etc/X11/xorg.conf /etc/X11/xorg.conf.old
Regenerating new GUI configuration file
#system-config-display
this command will regenerate fresh GUI and it will ask you for new resolution too, so set the new resolution to your requirement.