I have got following problem: after login LightDM doesn't appear. Before login the user-choose screen works fine. I can see only my wallpaper. Also I can run terminal (by ctrl+alt+t) and other and programs with it.
I have installed nvidia-current-updates (I don't have got nvidia-current installed). Also tried installing gdm but after choosing it as default display manager nothing happens. I already done apt-get upgrade and apt-get update.