Windows 8 build 8422 (fbl_woa)

6.2.8422.0.fbl_woa.120524-2000
	Build of Windows 8
OS family
Architecture	ARM32
Compiled	2012-05-24
Timebomb	2013-01-15 (+236 days)
Works in	QEMU
About
SKUs
	RT (CoreARM)
Key
	NFV72-RG2HG-7FTTP-8FJTB-FF848

Windows 8 build 8422 (fbl_woa) is a build of Windows 8, which was uploaded to BetaArchive on 19 February 2019. It is only available under the ARM32 architecture.

Installation[edit | edit source]

QEMU installation guide[edit | edit source]

Installation guide on QEMU:

Prerequisites[edit | edit source]

The following requirements used in order to install this build onto a virtual machine are listed below:

A copy of QEMU v6.2.0, modified for Windows RT compatibility
A version of the TianoCore EDK II firmware designed for ARM32 emulation (included above), to be placed in the QEMU installation directory under fw/QEMU_EFI_1512_driver1998.fd
One virtual hard disk image (for storing the operating system)

Precautions[edit | edit source]

Certain Windows 8 builds (such as 8330 (fbl_woa) or 8422 (fbl_woa)) may fail to properly load certain binaries on most startup attempts due to an emulation bug that causes the boot environment to read files incorrectly (especially the Hardware Abstraction Layer) causing an invalid checksum error, despite the files themselves being unmodified. This can be worked around by attempting to retry the startup attempt multiple times.

USB emulation is largely unstable and may result in all input devices failing to register any user inputs. To restore input, switch to the QEMU compatibility monitor (Ctrl+Alt+2) and run the following commands:

device_del kbd
device_add usb-kbd,id=kbd
device_del mice
device_add usb-tablet,id=mice

Instructions[edit | edit source]

Create the needed virtual disk image through the diskpart utility by running the below script; they will be created under a directory in the C: drive named ARM8. The partitions it will contain will be respectively mounted under drive letters F and P.

create vdisk file="C:\ARM8\HDD.vhd" maximum=65536 type=expandable
select vdisk file="C:\ARM8\HDD.vhd"
attach vdisk
convert gpt
create partition efi size=100
format quick fs=fat32
assign letter=F
create partition primary
format quick fs=ntfs
assign letter=P
exit

Deploy the image and apply the generic product key from the build's installation media by invoking the following DISM commands, then add the boot files to the EFI partition:

DISM /Apply-Image /ImageFile:"X:\path\to\install.wim" /ApplyDir:P:\ /Index:1
DISM /Image:P:\ /Set-ProductKey:NFV72-RG2HG-7FTTP-8FJTB-FF848 /AcceptEula
bcdboot "P:\Windows" /s F: /f UEFI

Eject the currently attached virtual disk from the machine, then paste and run the contents of the below script onto a batch file within the QEMU installation directory, replacing YYYY-MM-DD with the build's compile date:

set MAIN="C:\ARM8\HDD.vhd"

qemu-system-arm ^
    -M virt,highmem=false -cpu cortex-a15 -smp cores=4,threads=2 -m 2048 ^
    -device usb-kbd,id=kbd -device usb-tablet,id=mice ^
    -drive id=SD,if=none,file=%MAIN% -device sd-card,drive=SD ^
    -bios fw\QEMU_EFI_1512_driver1998.fd -device VGA ^
    -rtc base=YYYY-MM-DD,clock=vm ^
    --accel tcg,thread=multi

Continue installing the operating system through normal means.

Installation on Surface RT devices[edit | edit source]

Contrary to popular belief, this build is actually bootable, but it has only been tested on the Surface RT 1st generation. First you'll need to make a Windows RT 8.0 recovery drive, so the proper boot files can be added (mainly, a signed bootarm.efi). Next, you'll need to install the Secure Boot Debug Policy to your device. Enable test signing, mount the WIM, and follow the steps for registry and dll modifications. Commit your changes when done.

Alternatively, you can use the instructions here to integrate all the boot-critical drivers needed (especially the HAL extensions) so that the build actually boots. Use drivers from Windows RT 8.0 without updates for best results.

Without these modifications, the build will fail to boot with a 0x5C error.

After everything is done, make sure your BCD is enabled for test signing, and the build should boot successfully.