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The USB devices are not recognised in the BIOS...but are visible in Windows...I have both a USB thumb drive and an external SSD connected via USB. On the USB stick I have a version of Linux I wish to boot from. Any advice please ? I would expect to see the devices listed in the device boot selection...

Despite pressing F7 to get into the boot menu on startup and having three external USB devices connected I only see the option to boot from 1 the internal SSD, I seem unable to select the external USB boot devices from within the BIOS....any advice please ?

How do I select an external USB device to boot from instead of the internal SSD please ?