Old copy of Windows Core OS for the Polaris shell leaks

2 min. read

Published on January 3, 2021

published on January 3, 2021

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An old copy of the Polaris, the version of Windows Core OS designed for laptops, has leaked onto the internet, reports the WC.

The build is designed for ARM-based devices and dates from 2018, so, unfortunately, lacks a shell or any interesting apps.

The build can currently be downloaded at Archive.org and is PolarisOS Build 16299 (ARM32).

The uploader writes:

don’t ask me where I got this from.

Original Readme:
“This is PolarisOS. It’s a cancelled edition of Windows Core OS that was designed for Desktops and Laptops. This image is early enough to not include much more than the OS itself. It comes with no shell, and won’t load any.
You need an ARM device to boot this, and you need to sideload drivers before first boot. The wim is bootable, but you can also install it directly by applying index 1.

To install on a phone instead of an arm tablet, go to catalog.update.microsoft.com, find the latest firmware for your phone, download all MainOS cabinets for it, place all of them in a folder, and run dism /Image: /Add-Package /PackagePath:

To install on an arm tablet, get the tablet drivers, and run dism /Image: /Add-Driver /Driver: /Recurse

Upon boot, pressing the power button will shutdown the device, connecting the device over USB will expose a diagnostic interface, which you can use to open a command prompt shell afterwards”

No screenshots because I don’t have a compatible device for this build.

The build is not much than a curiosity now, but interestingly after a large number of direction changes, it is the desktop build of Windows Core OS which will be the one which makes it to devices in the end,after versions for dual-screened smartphones, dual-screened laptops and the Surface Hub were all cancelled.