Sophos firewall XG on Shuttle DS57U

Question

I'm trying to install the home edition of Sophos firewall XG on a Shuttle DS57U but whatever I try I get the Failed to load ISO error. 
 - USB stick created with Rufus 2.8 
 - USB stick created with Yumi 
 - USB stick created with win32writer 
 - USB CDROM burned ISO to DVD 
 Updated BIOS to latest version DS57U000.203 
 Anyone any suggestions?

HuberChristian · Accepted Answer

No suggestion unfortunatedly, but I have a Customer, whoi s using exactly that DS57U Device to run Sophos XG Firewall on it. So there, must be a Solution to solve this... 
 Have you tried RUFUS, and creating a DD Image instead of a ISO? This solved similar Issues in my case so far.