LXDM just restart when I login (Arch Linux)
 

When I boot into my Arch machine, LXDM starts just as it is supposed to. When I try to log in to any user account, the login form, restart buttons and such of LXDM disappears, but the wallpaper stays. Nothing more happens for a second, and then the forms and buttons come back. The wallpaper does not flicker or anything. So, I cannot log into my user accounts. I don't really know what's wrong, so if anybody has any clue...?

I recently updated my Arch installation from kernel 2.6.39 to 3.0.3 using pacman, might that have caused this problem? I am running openbox as my window manager, but have XFCE and FVWM-crystal installed as well. I cannot login to any of them, though. When trying to start openbox in single-user mode, I get an error saying "Could not open a display in environment variable DISPLAY". Starting lxdm in single-user mode gives same result as otherwise, unable to log in. I googled, but no solution came up. Anybody know what to do?

I think I have located which application is causing the problem. I reinstalled Arch on the same system but a different HDD, and got openbox working together with lxdm display manager. I installed tint2 and Conky, and had them load at startup using ~/.config/openbox/autostart.sh. I logged out, but Conky appeared at the lxdm login screen, and lxdm failed to log in next time I tried.

I have been trying to fix this using the single.user mode for a while now. X starts when I run startx and get into the default twm environment. If I use startx to start openbox, it does not load my config files properly, and therefore starts with standard menu and theme. If I start openbox or openbox-session from terminal, I get the following error:

I have been googling for a couple of hours, but without finding anything useful. I have read some suggestions that I should write a custom xorg.conf, but I have absolutely no idea what to put in it to get openbox running.