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I had 12.04LTS and recently decided to upgrade to 13.10. 12.10 wouldn't ever start up and all I could access was the GRUB and the terminal, so I upgraded to 13.10 from there. I have a cd with 12.04 on it but I do not have the others on a disk and I cannot make one because I do not have a cd large enough to make one. After 13.10 was installed, it worked alright. There were black bars around every field and I could not acess the terminal at all. I restarted it and after I put in my password, the screen goes blank and after a moment or so there would be two boxes that say something along the lines of a system problem being detected and I could move the cursor to click either cancel or report the problem. Nothing would happen after that, but by using ctrl + alt + t I could access the terminal. I looked at a few other topics that others seemed to be having the same problem as I did but all of the solutions that were being suggested didn't work for some reason. I don't want to reinstall the system because I couldn't create a backup of my files before this happened.