EFI boot fails


New Member
Feb 4, 2019
Hey all,

I' currently testing GPU passthrough via Proxmox, and the feedback is clearly positive (compared to KVM).
First, I've configured a Windows 10 VM to check if the GPU were correctly seen, and the answer is yes.

I have a Linux VM running on a old Ubuntu server, running KVM.

I want to "migrate" this VM, so I created a new VM in Proxmox, set the basic settings such as vCPU, RAM, network, and then changed the machine kind to q35 and the BIOS to UEFI

But I have an issue with the EFI boot, who fails :



I has the same kind of issue with EFI boot on KVM, but don't master it.

Would anyone have an idea on how to fix it ?
You cannot just change a BIOS installation of Windows to a UEFI one. But there is a tool that can convert a Windows installation from BIOS to UEFI. I found this Guide: https://www.windowscentral.com/how-convert-mbr-disk-gpt-move-bios-uefi-windows-10

I had to change the Disk Type to IDE in order for the windows recovery environment to recognize it.

If your disk is not of type IDE, first detach the disk, then edit it and set the Bus/Type to IDE. Don't forget to change the boot order in the VMs options.
Then follow the Guide.

Once you converted your VM you can change the BIOS type to OMVF (UEFI) and add the needed EFI disk.
After trying to get it booting again when the disk is set to SCSI (as I had it before) which proved to be a bit more tricky I would recommend to just install it fresh with the BIOS set to OMVF from the start if it is not too much of a hassle.


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