After a clean install of Ubuntu Karmic (9.10), on a box with an Nvidia card (1), went into “System” > “Administration” > “NVIDIA X server settings” and changed configuration to TwinView (I’m using dual monitors), which worked, but saving the configuration returned:
Failed to parse existing X config file '/etc/X11/xorg.conf'
Nothing further found in the logs. The solution was two-fold.