Comment 15 for bug 1190256

  // , The above answer "Copying the 3 files /usr/lib/syslinux/modules/bios/{libcom32,libutil,menu}.c32 to the root of the USB disk worked." worked for me.

I was trying to install ubuntu 14.10 x64 to a PNY device.

After you install Ubuntu 14.10 to your USB drive, run the following commands:

cd /usr/lib/syslinux/modules/bios/
cp libcom32.c32 /media/path/to/usb/drive/
cp libutil.c32 /media/path/to/usb/drive/
cp menu.c32 /media/path/to/usb/drive/

If you have any more questions about this, PM me.