・VM won't boot: stuck at "start boot option" (bootloader cause)
Hi, I'm pretty new to use Proxmox.
When I tried to virtualize my existing windows 10, I struggled with a boot loop and found this forum.
I met the issue stuck at "start boot option" after started VM.
But in my environment, it finally solved. (takes ~2days...)
so let introduce my case.
・Things I've tried
Sadly, these are didn't work in my case,
but some of them are partially recommended still.
・different ways to importing the disk
disk2vhd, with/without "prepare for virtual PC"
dd if=/dev/sda of=./DESKTOP-xxxxx.img status=progress, qm disk import 100 ./DESKTOP-xxxxx.img local-zfs -f raw
dd -> VDI (qemu-img convert)
・Proxmox VM hardware settings
[Hardware]
Processors Type: set x86-64-v2-AES
Machine: q35 -> i440fx, also changing the period version < 10.0
SCSI Controller Type: VertIO SCSI single -> Default(LSI 53C895A)
Hard Disk: IDE -> SATA (SATA preffered still)
BIOS: OVMF (UEFI) ->Default (SeaBIOS)
EFI DISK: deattach, then re-attach with uncheck "Pre-Enroll keys" option
・Proxmox VM options
OS Type: Microsoft Windows 11/2022/2025 -> 10/2016/2019
Boot Order (it's still important to re-order them)
[Others]
disabled secureboot from UEFI setting
disabled fastboot from UEFI setting
I'm so screwed, almost gave up to virtualize my windows.
・My solution
Then , I mounted ISO image of "Windows Install media" , and tried to repair imported disk.
prioritized boot from CD/DVD drive, open a windows RE > command prompt, tapping keyboard with a prayer,,,
I've noticed there's no files on EFI partition.
holy moly, who wiped my boot files!?
I can use windows 10 without any trouble, just wonder why..
anyway, I successfully started up my VM afterwards.
hope this works!
=============================
・Check disk volumes
Code:
diskpart
sel disk 0
list vol
it'll list up EFI partition (FAT32) with no assigned drive ltr(letter), it was volume 4 in my case.
mount EFI partition
Code:
sel vol 4
assign letter=b
exit
b:
bcdedit // showing bcd configure
dir
// ⚠️ if you see boot files exists, the fault might not be considered to bootloader. following procedure may risks damage your disk image.
//
mysystem mounted as bellow.
continue to create boot files.
D: Windows+Userdata, etc. (dir d:\Windows, dir d:\Users)
B: EFI Partition
Code:
b:
bcdboot d:\windows /l en-us // for my region /l ja-JP
bcdboot d:\windows /s b: /f UEFI // /f all option also available
dir // boot files should be created
bcdedit
dir EFI\Microsoft\Boot\ | find "boot" // bootmgfw.efi should be displayed
dir c:\Windows\system32\ | find "winload" // winload.efi should be displayed
bootrec /rebuildbcd // didn't work in my case
bootrec /fixboot // didn't work in my case
・optional repair
chkdsk /scan d:
dism /Image:d:\ /cleanup-image /restorehealth
sfc /scannow /offbootdir=b:\ /offwindir=d:\windows
also check these for further infomartion.
Download Windows 10 Disc Image (ISO File)
https://www.microsoft.com/software-download/windows10
How to Repair the EFI Bootloader on a GPT Hard Drive for Windows Operating Systems
https://www.dell.com/support/kbdoc/...indows-7-8-8-1-and-10-on-your-dell-pc?lang=en
Use the System File Checker tool to repair missing or corrupted system files
https://support.microsoft.com/en-us...em-files-79aa86cb-ca52-166a-92a3-966e85d4094e
=============================
please forgive me if there are any mistakes, including grammars!
Thanks for reading.
