Too much in this thread for me to have read it all, but I have handled these often. If you're downtown on Sunday call me (write privately for phone #) and I'll look at it with you. The things to do from a virtual console are to sudo apt /etc/init.d/lightdm stop sudo apt /etc/init.d/gdm3 stop sudo apt /etc/init.d/kdm stop sudo apt /etc/init.d/xdm stop and so on for any *dm. Then you try your startx. You can also try a restart on the less flakey display managers, like gdm3 ("sudo /etc/init.d/gdm3 restart") If you are experimenting with our GUI running you can run "startx -- :2" (or :3 or higher) to see what happens. For this list attaching the full /var/log/Xorg.0.log might be useful, as well as transcripts of startx with different displays like :2 or :3. On thing I'm not clear on is what really happens when you power on the computer. Your original email (I was unable to follow all the followups) does not make it clear if that first login you do is graphical or on a virtual text console. If the former, then the whole rest of the message is strange because starting X from an alread-graphical situation is not the thing to try. If that first login is on a virtual text console then your situation seems to be that you booted and it came up with vt1 instead of vt7, but at the same time automatically logged you in as guest on vt7. I have never seen that, and it smells of some weird mucking with user accounts. Make sure that guest is not set to automatically log in. Among other problems with the precision of this problem report is that you don't mention what desktop is your default, and which one comes up when you go to vt7 and are logged in as guest. Maybe it's in the many later messages. Anyway, call me up if you're downtown and we'll experiment.