Windows Core OS spotted in Windows 10 support document

Windows 10X Shell
Windows 10X Shell (Image credit: Windows Central)

What you need to know

  • Windows Core OS is mentioned in an official Windows 10 document from Microsoft.
  • Windows Core OS will run devices including the HoloLens 2 and Surface Hub but has not been officially discussed by Microsoft.
  • An potential upcoming device codenamed Centaurus reportedly runs Windows Core OS.

A support document for Windows 10 version 1903 mentions Windows Core OS several times. Microsoft has never officially mentioned Windows Core OS in a statement or announcement, even though the operating system will power two devices that have already been shown off, the HoloLens 2 and the Surface Hub 2. Windows Latest spotted that a support document (opens in new tab) for Windows 10 version 1903 mentions Windows Core OS specifically.

The support document was published in April of this year but was only spotted recently. The document states that it takes 274 minutes to read and is one of many support documents from Microsoft, so it's not surprising that a few short mentions of Windows Core OS went unspotted for months.

The document is for basic level Windows diagnostic events and field for Windows 10. Underneath the subheading "Common Data Extensions.utc" the document lists three items related to Windows Core OS:

  • wcmp The Windows Shell Composer ID.
  • wPId The Windows Core OS product ID.
  • wsId The Windows Core OS session ID.

As pointed out by Windows Latest, Github shows that the mentions of Windows Core OS were added April 19, 2019.

Windows Core OS is a version of Windows with a universal base that can work across different devices. There are several "flavors" of Windows Core OS including versions for laptops and foldable PCs, collaborative displays such as the Surface Hub 2, and Windows Mixed Reality devices like the HoloLens 2.

How to watch the Microsoft Surface event live stream on October 2

Our Senior Editor, Zac Bowden, created an extensive breakdown of Windows Core OS, including explaining several related components like CShell. There's a chance that a variant of Windows Core OS will be mentioned or shown off at the Surface event on October 2, 2019.

Sean Endicott
News Writer and apps editor

Sean Endicott brings nearly a decade of experience covering Microsoft and Windows news to Windows Central. He joined our team in 2017 as an app reviewer and now heads up our day-to-day news coverage. If you have a news tip or an app to review, hit him up at (opens in new tab).

  • Beginning to feel like vaporware.. Lol
    Time to see some new devices running some new software. Things seem like they've been kind of stagnant for a while now.
  • Well we've gotten glimpse of the OS.
    And we know it coming to the hololens 2 and the surface hub 2x
  • Vaporware means it has been announced but seemingly never comes out. You only know about Core OS because we've reported on it without Microsoft consent. 😏
  • Touch'e... Well, we only have two very far apart chances to see it first.. One, the upcoming Surface event, and 2, Build 2020, 🤷🏾‍♂️🤷🏾‍♂️
  • Partially true. Reporting on news site is one thing. Being a software engineer like me and finding references in Windows APIs is a whole another thing. In a developer relationship with Microsoft (or any other company) you have full right to know what API does what, not to say it's vital to know it, and to see full explanation in or the dying MSDN at least. Much time has passed since the first references of WCOS in Windows code appeared and there is still no explanation what it is and what it does anywhere by Microsoft officially. In order to be committed to a software vendor and develop software for its platform you have to know the **** out of its platform to be efficient and professional enough
  • Something that hasn't actually been announced can't be vaporware. Then again, Microsoft only just mentioned the idea of a modern OS only a few months ago while being entirely vague about it. With that said, hopefully they talk about the existence of this at the upcoming event.
  • Open source vaporware? Unlikely
  • Vedi nice, its about time!
  • After the redesign hopefully being well thought out, there is only really two things I want from Microsoft and Windows. The Xaml taskbar on Windows Lite to be configurable to be a dock like the one on the iPad or like the one in all the concept art people have made or like the one that ObjectDock, RocketDock, and NexusDock have all made software for and the other thing I'd like to see is a phone like the Galaxy S10E running Windows Lite.
  • I want the whole shell part to be UWP based so it can be easy to create shells for Windows Lite, and then I want to be able to port Windows Lite to all the poor hardware that were left out in the cold like droves of WP phones and Windows RT tablets.
  • Windows Core OS is so... well... "core"! It will be Nadella's penultimate achievement in an already brilliant run to draw developers!
  • Still haven't lost my hope for a windows phone & a potential surface watch.