"An unknown error ocurred" during installation on empty partition

[apparatus]

Try to compare the ISO image to the USB disk like this to see where was it modified:

QubesOS test media always fails

Check the binary changes between the images: cmp -l file1.bin file2.bin | gawk '{printf "%08X %02X %02X\n", $1-1, strtonum(0$2), strtonum(0$3)}'

E.g.:

cmp -n $(stat -c %s Qubes-R4.2.2-x86_64.iso) -l Qubes-R4.2.2-x86_64.iso /dev/sdd | gawk '{printf "%08X %02X %02X\n", $1-1, strtonum(0$2), strtonum(0$3)}'