Thank You for the Clarification, It does seem to be an isolated issue with 2 users of Asus Z390 Boards, i had a Similar issue with a MSI Z390 Board and even EmuVariable wasn't successful in my case, i gave up and switched to a working Z370. I'm sure @errorexists will see your post, And the frustration with him is the fact the board he has was a gift from his children, which i think as to why he gets upset with the fact it doesn't work with or without the workaround. checking NVRAM after bootup doesn't indicate its working and yes i think there is some issues with the way the UEFI is getting stuck in a loop as you said. I personally don't see any advantage over the Z370 to upgrade to Z390 as the Z370 along with Z97's are most compatible. I will today make a New EFI for him and get him to post me a log so that we can see for sure what the issue is. if this is something you are willing to look at.