I often find that's the cause or the machine's BIOS really didn't support this USB booting.
Something's off, but I'm not there to see what. No machine, make, model and I fear you are creating many posts on the same issue. Details are lost when you do that.
Many thanks...I have reset boot order to make the USB drive first choice. I've turned it off and back on again, restarted with USB stick with OS on it plugged in but does not seem to be picking it up. I made sure the USB stick was formatted and I made sure I saved the boot order change. How can I get it to actually reboot from the USB stick now?
Many thanks

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