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in order to fix a problem with the setup of the screen brightness I try to create a xorg.conf

This is done by the command X -configure right?

Trying to run this command as root, I will get:

Fatal server error:
Server is already active for display 0
    If this server is no longer running, remove /tmp/.X0-lock
    and start again.

Trying to run this command in recovery modus, I will get the same. After remove the mentioned file I get the error: cannot create file /tmp/.X0-lock Just to make sure: Yep I have the rights as I am logged in as root.

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I`m with the same problem and after do this in the 3. sudo Xorg -configure show List of video driver ... ... ... (++) Using config file? "/root/" (==) Using system config directory "/usr/share/X11/xorg.conf.d" Number of created screens does not match number of detected devices. Configuration filed. Server terminated with error (2). Closing log file. Please help me!!!!! – Jamal Malik Mar 14 '13 at 1:06

I think you shall have to stop the xserver first. Try this:

  1. Open a Terminal with CTRL+ALT+F1 and login
  2. sudo stop lightdm (or kdm or gdm instead of lightdm if you installed kubuntu or GNOME shell)
  3. sudo Xorg -configure
  4. sudo start lightdm (or kdm or gdm instead of lightdm if you installed kubuntu or GNOME shell)
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