Possible Duplicate:
Boot from USB on a Macbook
I tried to make my USB drive for Ubuntu using unetbootin but after it finished loading the os on usb drive, i get this message: "The created USB device will not boot off a Mac. Insert it into a PC, and select the USB boot option in the BIOS boot menu." Anybody has any idea?
Mac OS requires that you have an OSX install on the USB media in order to boot from it. I don't particularly care for this practice, but it is true. See the previous post on the matter here.