Zitat von mpca am 26. Februar 2021, 21:36 Uhr

I was able to install XG Home Version an Sophos XG Appliance.
So the steps I have followed were:

Creating a USB drive with Debian latest release
Boot the XG from USB drive and install Debian (delete all patitions), yes Grub will be the Bootloader (sophos bootloader is overwriten)
unplug the usb drive with ubuntu and then plug the pen drive with XG SW Version
Power on the device and boot from usb drive
Appliance will be recognized but SW Installation will continue.
Install the XG version