Qubes_dom0-root does not exist - preventing boot after ungraceful shutdown

[apparatus]

Can you post the errors that you have in rdsosreport.txt?
Maybe only root thin pool was corrupted and you can try to recover it.

If you’re able to decrypt the LUKS and your LVM is not corrupted then you can try to get the data from the qube like this:

Paid help: uefi boot items disappeared, re-added and never booted again!

I can only give you approximate untested instructions: Assuming: /dev/sda3 - old Qubes OS encrypted LVM /dev/sdb1 - temporary backup drive and assuming its filesystem support creating sparse files (e.g. ext4) (Sparse file - ArchWiki) or has enough space to contain the VM raw images Mount your backup drive, decrypt old Qubes OS system and activate VG: mkdir /mnt/qubes-backup mount /dev/sdb1 /mnt/qubes-backup mkdir /mnt/qubes-backup/old-qubes-os-backup cryptsetup luksOpen /dev/sda3 luks-old-q…

But you won’t be able to backup the qubes themself to restore them in new Qubes OS late, you can only get the data inside the qubes like this. You’ll have to recreate the qubes in the new Qubes OS installation manually.