After I finished working, I made the usual update that ubuntu every now and then ask to do. Please notice is update, I'm not upgrading the distro. After it finished, it asked for a reboot which I did. Boom, it won't restart on graphical mode. The XFCE window appears for a very short time, and then everything goes black and I get a console logging. I cannot start the lightdm, it just switches session to the 7th and stands there, waiting.
Where can I start looking for what went wrong? I already started to make a backup, but I really don't want to have to resintall everything...