I've been using unetbootin for quite some time now and never had any problems like what's going on now. The problem I'm having is when I use unetbootin to make BackTrack boot off a usb everything goes fine loading the image onto the USB stick, then it comes time to reboot, so I reboot. This is when the problem starts. I choose to boot off usb drive within the bios (like i've always done) and the computer just locks up and becomes unresponsive. At this piont the only option I have is the power button. It does this on multiple laptops. I've tried using different usb sticks, loading BackTrack via unetbootin on different computers, tried different Versions of BT (BT3, BT4-pre-release & BT4-pre-final), even reformatting the sticks to FAT and FAT32. I tried googling this problem with little results. I am out of ideas. Does anybody have any suggestions? Thank you.

BTW i'm using the windows version of unetbootin.