I'm using YUMA
to create a multiboot drive out of my 16gb Patriot XT flash drive. I'm using the Windows 7 SP1 x64 image provided by digital river and a Backtrack 5 Gnome x64 image. This isn't my problem though.
When I boot my computer without the USB drive in any port, it pops up in the boot menu. When I plug in any USB flash drive, though, and then go into the boot options, it's gone. Essentially the only time it will give me the option to boot from a flash drive is if there is no flash drive in the port. It doesn't matter whether the drive contains a bootable image or not.
Boot order is as follows:
Legacy USB support is disabled since enabled causes booting with the drive in at all to lockup during POST.
Any ideas on what could be causing this?