Firefox Failed to Launch D-Bus Daemon

After some upgrades on my Arch Linux, my Firefox suddenly raised an error dialog on startup:

, where the details button showed me:

Failed to contact configuration server; some possible causes are that you need to enable TCP/IP networking for ORBit, or you have stale NFS locks due to a system crash. See http://projects.gnome.org/gconf/ for information. (Details - 1: Failed to get connection to session: /usr/bin/dbus-launch terminated abnormally without any error message)

Through command ps aux | grep dbus-daemon, I found out that there are many processes started. The problem is that Firefox cannot communicate with dbus-daemon. After goolgling, the communication is established by setting environment variable DBUS_SESSION_BUS_ADDRESS. It is weird that dbus-daemon was started on-demand, but Firefox had not got the address. So I tried to start dbus-daemon myself when I logged into windows manager, and Firefox no longer reported such error.

Because I use SLiM to start the windows manager, I can add following code in .xinitrc to start dbus-daemon and setup the environment variable correctly (via Arch Wiki). Depending on the startup method, these code may need to add to .xsession, .Xclients or other init files.

# D-bus
if which dbus-launch >/dev/null && test -z "$DBUS_SESSION_BUS_ADDRESS"; then
    eval `dbus-launch --sh-syntax --exit-with-session`
fi

Also see a more complicated version written by me here, which store variables in file and avoid starting multiple instances of dubs-daemon.

Related posts:

1. Use GCC 4.1 in Arch Linux
2. Run `kill-emacs-hook’ in Emacs Daemon