I have been trying to dual boot my mid-2012 Macbook Pro running OSX Mountain Lion with Ubuntu 12.10 with a disk and a USB, and none of them are working. I have used disk utility to partition my hard drive for linux and burn the .iso image to the external drives (usb and dvd).
The only thing that happens at the end, is that the disk becomes useless by giving this message: "The disk you inserted was not readable by this computer."
I have gone into terminal and burned my iso through terminal, too. I also tried to do it with Ubuntu 12.04 instead of 12.10 with the same outcome.
BTW, for reference, I did the exact same thing as explained in this tutorial, except they can burn the dvd and I can't. Maybe this Ubuntu download is meant for Windows?
Also, I have rebooted my mac holding c and also tried selecting the cd by holding the option (alt) key. Nothing shows up.
I really don't know what the problem is. I wasted 5 dvd's, 2 cd's, and a USB. Can someone please help me out? Thanks!