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I have a couple of systems

  1. Running Suse Linux 11.4 & XDM Display manager .
  2. Red Hat Linux & Gnome

in both these systems when I log in as root user I am able to execute any X application like xterm , xclock etc .

However the trouble is when I login as a non root user I get the following error


No protocol specified

Error: Can't open display: :0

I see the following error in the logs

  1. No messges in /var/log/Xorg.0.log in case of Suse Linux
  2. The following error message in /var/log/Xorg.0.log in Red Hat
    AUDIT: Thu Nov 10 16:02:06 2011: 8659 Xorg: client 35 rejected from local host

I tried googling the error but couldn't find anything to help me.

This post describes the problem but did not fix my issue .

The surprise is that on my friends machine things work perfectly even for a non root user.

I suspect that there is a setting issue on my system. Is there some configuration that needs to be done to allow the non root users to execute X applications on a xdm system?

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migrated from Nov 10 '11 at 13:51

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