Can't boot in legacy mode! Helppp!

[Luddy]

A little bit of background story line fun, I was originally running Unraid through UEFI mode just fine, but then stumbled upon the dreaded Code 43 error when passing through my GTX 1080ti to my Windows VM. I did every fix I could personally find for that, disabling the hypervisor setting, dumping my own GPU rom from my bare metal windows install (removing the header of course) and applying that, installing the drivers anyway despite the Code 43, enabling the multifunction ability by editing the XML to match both my Sound and Video from my GPU to the same slot, but none of that worked. I stumbled upon the conclusion from Spaceinvader one that it could possibly be because of the lack of Legacy booting and rather UEFI boot.

 

I have not been successful in getting to boot from Legacy, and have gotten frustrated enough that I perhaps reinstalled Unraid unnecessarily onto the USB again and wiped my own config on purpose by thinking that not check boxing the UEFI boot option would maybe fix it. It did not. Lol. (I also made sure to run the make_bootable.bat file when reinstalling.)

 

I have a Asus Z270-E motherboard, which has an annoying BIOS (as most do.), I have disabled the secure boot by deleting the keys, setting the CSM to Legacy only, setting the USB I am booting from to Forced FDD, Floppy, Auto, have tried on the USB-C port, my mobos USB 3.0 and 3.1 ports, and my front case 2.0 ports, have moved it to the top of the boot list everytime I tried those different settings, and tried booting from each setting configuration by boot menu, but none of it has worked.

 

Everytime I boot I either get a black screen that promptly sends me back to the BIOS to stare with discontent, or it gibbers on about... "This device is not bootable. Make sure you have a bootable floppy and press any key to try again..." which is why I also tried to Forced FDD and Floppy USB override settings.

 

Any ideas? Any help or pointing in the right direction would be GREATLY appreciated. Thank you guys!

Edited April 12, 2020 by Luddy

[Squid]

With most BIOS, you set the boot order so that the hard drive is the first (and ideally, the only) boot device, and under the hard drive priority, you select the flash drive as the hard drive (select the "normal" flash drive, not the UEFI one)

[Luddy]

That’s essentially what I’ve done, I usually go fully into the boot menu device selector anyway and boot directly to the USB from the non UEFI partition. Still gives me that same error. Floppy yadda yadda. 

[Squid]

Pull the stick.  Check for corruption on a windows box (check disk).  If need be, re-run Make_bootable.bat (it's in the root of the flash) as administrator and try again.