My lubuntu crashed, and after reboot, when I log in on any of my administrator accounts, it would show the default wallpaper and the mouse pointer. Also, can't open the terminal or any other keyboard shortcuts. I can log in using the guest account, but it doesn't have permission to do most actions. I were also able to log in my account using openbox mode, but most admin actions were supressed too. I can't create a new user (I was hoping the new user could log in OK, since the guest could. The only option is to re-download and re-install lubuntu, but I don't have a fast enough web connection (and I would also lose all my data). What can I do to reset my user, or create a new one?