Comment 3 for bug 816906

Same problem here on ASUS eeePC900. This is a machine that can't run unity (GMA900, Celeron 900)

With eternal monitor plugged in, after ctl-alt-F1 to terminal and typing in startx, error box with "failed to load session gnome" and logout button shows.

Disconnecting external monitor, X-server tries to start but gets into "no protocol specified" loop.

Rebooting and attempting the fix specified in Launchpad 804171 resulted in
    liblightdm-gobject-1-0_0.9.2-0ubuntu1_i386.deb
and
    lightdm-gtk-greeter_0.9.2-0ubuntu1_i386.deb
not found in ca.archive.ubuntu.com/ubuntu/pool/main/l/lightdm