M:
Good news is you are close to having it installed. When/how do you get
this error, while it is preparing templates or once you've logged in to
Qubes? If you can get to a dom0 terminal, check "lspci" and it will tell
you what device is on 0000:00:1f:6. The fix is similar in either case-
temporarily disable the problem device (likely a wifi card) in UEFI
config, then repeat either the full install or if you can get to a dom0
terminal "sudo /usr/libexec/initial-setup/initial-setup-graphical". Once
you are able to login without it complaining, re-enable the problem
device, and add it to sys-net with no-strict-reset per
https://www.qubes-os.org/doc/pci-devices/#pci-passthrough-issues.