S.V.

Hello everyone, I am trying to boot Unraid 7.3.1 on my system from a USB flash drive that I created using the official Unraid USB Creator. My motherboard is an ASUS ROG Strix B450-F Gaming. In the BIOS, I have already disabled Fast Boot. CSM is also disabled, and Secure Boot is set to Other OS. With CSM disabled, the USB stick does not show up as a bootable device at all. If I enable CSM, the USB stick does appear as a boot option, but when I try to boot from it, I immediately get the error message: Missing Operating System I also checked the folder structure on the USB stick. The EFI folder has the correct name and does not have the trailing hyphen at the end, which is often mentioned in related error reports. Other operating systems, such as Windows and TrueNAS, boot without any issues on this same machine using the same BIOS settings. Does anyone have an idea what could be wrong or what else I should check? Thanks in advance.