Cannot boot from MBR device

Message Topic Search Topic Options Post Reply Create New Topic Printable Version Translate Topic

   Z370 Taichi BIOS 3.40 8700K

I am having a problem when trying to boot from an MBR device whether it is a HD or USB.
The message I get is to select the proper device to boot from and try again.
I can see both entries for the device in the boot selection menu. But the only one I can boot from is UEFI. For example, If I create a Bootable USB using RUFUS and select MBR/UEFI in the creation, I see two entries for the drive but I can only boot from the UEFI entry. I should be able to boot from either.

CSM is enabled in the BIOS. I tried to reflash the BIOS with the same version in case it was corrupted but it would let me.

 I know this was working a while back as I was able to install windows in MBR.
mode. The reason I wanted MBR mode was I have three copies of windows on three different drives and select the one I want by F11. I can no longer boot the MBR drives.

Author	Message Topic Search Topic Options Post Reply Create New Topic Printable Version Translate Topic
Lenster45A Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 24 Aug 2019 Location: Naples fl Status: Offline Points: 104	Post Options Post Reply Quote Lenster45A Report Post Thanks(0) Quote Reply Topic: Cannot boot from MBR device Posted: 23 Aug 2020 at 4:15am
	Z370 Taichi BIOS 3.40 8700K I am having a problem when trying to boot from an MBR device whether it is a HD or USB. The message I get is to select the proper device to boot from and try again. I can see both entries for the device in the boot selection menu. But the only one I can boot from is UEFI. For example, If I create a Bootable USB using RUFUS and select MBR/UEFI in the creation, I see two entries for the drive but I can only boot from the UEFI entry. I should be able to boot from either. CSM is enabled in the BIOS. I tried to reflash the BIOS with the same version in case it was corrupted but it would let me. I know this was working a while back as I was able to install windows in MBR. mode. The reason I wanted MBR mode was I have three copies of windows on three different drives and select the one I want by F11. I can no longer boot the MBR drives.
	Len