How to install Win7 32-bit in UEFI mode?

Hi everyone!

I’m trying to install Windows 7 32-bit on UEFI system.

The only helpful result from Google is Windows 7 x86 porting 32-bit UEFI boot - BetaArchive

Also saw some simmilar posts but about Windows XP, like How to switch XP over to winload bootloader? - #5 by Gelip

What I have done:

  • Installed Windows 7 with DISM++
  • Copied Windows/System32/winload.efi from Windows 8.1 installation
  • Created boot entry with EasyBCD

It loads into 8.1 OS selection screen, I select Windows 7, it reboots and fails with error like OS can’t be loaded because signature of ntoskrnl.elf can’t be verified.
If I load with disabled signatures for drivers (from F8 screen), it says that ntoskrnl.elf can’t be found or corrupt (it exists on the drive).

If I replace ntoskrnl.elf (which I think is a kernel so this is pointless) with one from Windows 8.1 it says that signature of some dll can’t be verified.

What I have not tried (will try soon, sorry)
- To use maharmstone/quibble from GitHub (sorry, only 2 links per post is allowed)

The device I want install onto is Samsung ATIV Smart PC 500T.

I will be very grateful for Your help!

Edit by Fernando: Thread title specified

There was no official Windows 7 x86 images boot support for UEFI machines, the system must be set as Legacy (CSM ON/AUTO/Win8WHQL OFF/etc…) disabling EFI payloads.
Can’t remember if there’s a Bootloader for old x86 OS, for loading into UEFI systems.

Probably UEFISeven 32-bit and files from Windows 8 Developer Preview 32-bit will allow you to boot Win7 32-bit on UEFI 32-bit
I’m try test in VMware and you have to run from the F8 menu and select Disable Driver Signature Enforcement
You also need a kd.dll file and some MUI files - I don’t know which ones yet :wink:

WinDbg log:

BGFX_ERR: Failed to load MUI resource (0xc000000f)!

P.S. Win8DP x86 ISO is not UEFI bootable. To test in UEFI you need fix ISO:

oscdimg_2.56 -lWindowsDeveloperPreview -t01/28/2024,16:30:00 -u2 -h -o -m -udfver102 -bootdata:2#p0,e,bF:\boot\,e,bF:\efi\microsoft\boot\efisys.bin F: dp8efi.iso

OSCDIMG 2.56 CD-ROM and DVD-ROM Premastering Utility
Copyright (C) Microsoft, 1993-2012. All rights reserved.
Licensed only for producing Microsoft authorized content.

Scanning source tree (1500 files in 537 directories)
Scanning source tree complete (1525 files in 544 directories)

Computing directory information complete

Image file is 3104702464 bytes (before optimization)

Writing 1525 files in 544 directories to dp8efi.iso

100% complete

Storage optimization saved 150 files, 74176512 bytes (3% of image)

After optimization, image file is 3035060224 bytes
Space saved because of embedding, sparseness or optimization = 74178560

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Thanks for your help.

I’d like to ask some questions:

  1. As I understand, bootmgr and EFI folder is needed to boot from UEFI (BIOS), so it will work without them while I still using loader from 8.1 on another volume?

  2. Why do I need to make Win8DP ISO bootable if I only use some files from it (like winload.efi)

  3. and files from Windows 8 Developer Preview 32-bit

    Can You please list what files I exactly need, because for now I have only used winload.efi and I am novice in this topic, so I am not sure.

  4. Does Win8DP have any special features why it works and files from my 8.1 does not?


I don’t know if Win8DP files will help, but I’m 90% sure it will. Therefore, I made a UEFI bootable ISO to install Win8DP under VMware in UEFI32 mode and check what files it requires to boot.

I copied the entire EFI folder from Win8DP ESP partition to ESP on Win7 and from Win8DP NTFS Windows\System32\Boot + winload.efi + en-US with winload.efi.mui to NTFS Win7 but still error in WinDbg :frowning_face: :

BGFX_ERR: Failed to load MUI resource (0xc000000f)!
1 Like

There is also winload.efi.mui at C:\\Windows\System32\en-US\winload.efi.mui

+ C:\\Windows\Boot\EFI\en-US\bootmgfw.efi.mui
As we also use bootmgfw.efi in boot process I think it may be required.

I checked all locations and files and still error BGFX_ERR but the system loading continues with black screen - I see the HDD icon flashing.


How have You resolved “Windows cannot verify the digital signature for this file \windows\system32\ApiSetSchema.dll”?

If I try to open advanced boot options (to disable signature verification) it also BSODs with the same message.

P.S. I have unpacked Win7 onto drive + created EFI loader from Win8DP (with dism and esdboot).