Is Windows 7 x64 UEFI install even possible?

Hi everyone,
i joined this forum because i found a lot of interesting information here regarding Windows installations and unattended setups.
I've been in I.T. for 15 years installing windows since 3.1
We now are a a crucial step in Microsoft Windows life where all the computers with USB3.0 support, UEFI only and no legacy BIOS support are not compatible with Windows anymore.
When you try to boot off a USB you get:
\EFI\Micosoft\Boot\BCD error with a status of 0xc000000d
The latest hack i tried from a USB was to get all the Windows 10 setup files but replace the install.wim with the Windows 7 one.
When you do this, the install works and the windows setup files are laid down on the hard drive but after reboot you get the same error.
BCDEDIT doesn't help so the only thing i can think of is to mess around with the OSCDIMG.exe options to create a purely efi .ISO and see if that works.

Just wondering, has anyone here ever gotten this to work?
By the way, the unmodified Windows 7 Microsoft ISO boots up fine in a system where UEFI is on and secure boot is off, but from USB you get that error, which leads me to believe the OSCDIMG might be the key.
Anyway i wanted to get your thoughts and if i get something working i'll post a guide here because this site is useful and might help other people in the future.

Thanks.

The latest on this for today is that if i burn the unmodified Windows 7 Microsoft ISO onto a DVD then i don't get the \EFI\Micosoft\Boot\BCD 0xc000000d error but if i burn the same ISO onto a flash drive with rufus, then i do get the error.
So this issue may not have to do with OSCDIMG but with rufus and the way it formats the flash drive.
I'll test on this tomorrow by using Microsoft's tools (Diskpart) to prepare the flash drive instead of Rufus.

Yes of course, I used Rufus in GPT mode only where it creates a FAT32 partition and you also need to split the install.wim by the way if its larger than 4gb.
So the issue may be specific to Windows 7 and Rufus because when I burn a Windows 10 ISO with Rufus, I don't have this problem.

The problem is that Windows 7 calls BIOS INT10 even when it's booting from UEFI, no matter what video mode the system supports. Windows 7 works at UEFI mode as long there is INT10 support in the firmware.

https://msdn.microsoft.com/en-us/lib...or=-2147217396

Windows 7

◦ Support UEFI 2.0 or later on 64-bit systems. They also support BIOS-based PCs, and UEFI-based PCs running in legacy BIOS-compatibility mode.

◦ Support on Class 2 systems running in legacy BIOS-compatibility mode by using a CSM, so they can use the legacy BIOS INT10 features.

◦ Are not supported on Class 3 systems, because these operating systems assume the presence of legacy BIOS INT10 support in the firmware, which is not available in a Class-3 UEFI implementation.

I've made a tutorial on how to install Win 7 on new MB.
Create a Windows 7 USB flash installation with new drives for new MB's

Osprey said:

The problem is that Windows 7 calls BIOS INT10 even when it's booting from UEFI, no matter what video mode the system supports. Windows 7 works at UEFI mode as long there is INT10 support in the firmware.

https://msdn.microsoft.com/en-us/lib...or=-2147217396

Windows 7

◦ Support UEFI 2.0 or later on 64-bit systems. They also support BIOS-based PCs, and UEFI-based PCs running in legacy BIOS-compatibility mode.

◦ Support on Class 2 systems running in legacy BIOS-compatibility mode by using a CSM, so they can use the legacy BIOS INT10 features.

◦ Are not supported on Class 3 systems, because these operating systems assume the presence of legacy BIOS INT10 support in the firmware, which is not available in a Class-3 UEFI implementation.

That is VERY interesting. Thank you. But how do you explain the situation where it works from DVD but not from USB?

Megahertz07 said:

I've made a tutorial on how to install Win 7 on new MB.
Create a Windows 7 USB flash installation with new drives for new MB's

I'll take a look at your tutorial. Thanks!