MSI Z270 A Pro usb boot Problem

Hi Gays,
I have a problem with my motherboard MSI Z270 a pro, when i try to boot my RIG in USB BOOT to install simplemining system, i have changed all setting in bios but don't work
Setting:
usb legacy support >> enable
fast boot >> Disable
Secure Boot >> Disable
Priority Boot >> USB Hard disk
try to use menu boot to show list device but my USB Hard disk dont exist in list.
put my USB in all ports 3.0 and 2.0 (not work)

Please help me.

Does the stick boot on other computer? Tried to make another stick, different brand or so...?

Yes, USB key work perfect in my seconde computer ASUS

Try another brand/size stick some can be tricky on some. Newest BIOS on mb too? Uefi boot disable?

Thank you, i will try with another USB Disk

same problem, the USB Disk dont exist in Boot Devices List

Disable uefi, legacy bootmode or so.

Had the Same Problem you need to use a USB 2.0 Drive spent a whole day trying to figure this out, When I read about the USB 2.0 Issue I gave up and just copied the Windows 10 Install files straight onto my HDD and then booted the PC up it installed off the HDD with no Problems.