First, I have looked through the suggested questions that may have an answer, but nothing seems on point.
I have a dual boot Ubuntu 14.04/Windows 7 system. I have decided to play around with some other distros and loaded one onto a USB stick with unetbootin. It won't boot. When the GRUB selection menu comes up, there is no "new" option to boot from the USB, unlike the previous GRUB when I was running 12.04.
The USB is selected as first priority boot, the cd drive second, and the hard drive 3d in bios.