Windows Sirius OS

= Windows Sirius OS =
== Windows Sirius OS ==
=== Release date ===
June 12, 2021
=== Created by ===
Microsoft
=== Developer ===
Microsoft
=== OS family ===
Windows Sirius
=== Source model ===
Closed-source
=== Update method ===
Windows Update
=== Kernel type ===
Hybrid
=== Latest version ===
25H2
=== State ===
Supported
=== Support ends ===
Mainstream support ends June 13, 2025
Extending support until January 12, 2029
=== Codename ===
Sirius
=== Final name ===
Windows Sirius OS
Windows Sirius OS (codenamed Sirius) Windows Sirius OS is designed as a touch-centric operating system. In earlier developer versions, it was indicated as a member of the Windows Core OS family. However, Microsoft decided not to include it in the Windows Core OS family, likely due to differing conceptual approaches.
== Contents ==
* 1Features
** 1.1Desktop
** 1.2Windows Subsystem for Android
** 1.3File Explorer remake
** 1.4Copilot
** 1.5Widget
* 2Development
* 3Builds
** 3.1Windows Sirius build 19561sr(Dev)(2020-02-06)
*** 3.1.1Bugs and quirks
** 3.2Windows Sirius build 19630(Dev)(2020-05-14)
*** 3.2.1Bugs and quirks
** 3.3Windows Sirius build 20174(Dev-1)(2020-07-17)
*** 3.3.1Bugs and quirks
** 3.4Windows Sirius build 20257sr(Dev-2)(2020-11-6)
** 3.5Windows Sirius build 21284(Insider Preview)(2020-12-5)
*** 3.5.1Bugs and quirks
** 3.6Windows Sirius build 21327(Insider Preview)(2021-02-26)
*** 3.6.1Bugs and quirks
** 3.7Windows Sirius build 21380(Pre-RTM)(2021-5-11)
*** 3.7.1Bugs and quirks
** 3.8Windows Sirius build 21400(RTM)(21H2)(2021-5-12)
** 3.9Windows Sirius build 22620(Update)(22H2)(2022-8-3)
** 3.10Windows Sirius build 22630(Update)(23H2)(2023-9-28)
** 3.11Windows Sirius build 26100(Update)(24H2)(2024-4-5)
** 3.12Windows Sirius build 27100(Update)(25H2)(2025-6-29)
* 4Gallery
== Features ==
=== Desktop ===
* You can place widgets on the desktop, but applications cannot be placed on the home page; they can only be positioned on the second page and beyond.
* The search bar(Activity Block) is located at the bottom of the desktop, and on widescreen displays, it is positioned at the top. When listening to music, you can swipe left to control the music.
=== Windows Subsystem for Android ===
* In earlier developer versions, it was referred to as "Android on Windows".
* There are two modes: Android On Windows and Windows Subsystem for Android. Android On Windows technology directly translates Android apps, while Windows Subsystem for Android simulates the Android environment.
* In devices with poorer performance, only AOW (Astoria) can be used.
=== File Explorer remake ===
* The redesigned File Explorer looks similar to Windows 11's, although Windows 11 had not been released at that time.
* Setting "old" to 1 in the registry key "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer" will revert the new version of File Explorer back to the old version.
=== Copilot ===
* In the 23H2 version, a feature was added where swiping left on the homepage opens Copilot, which is identical to the Copilot in Windows 11 23H2.
* On devices with better performance, Copilot can be opened in "device generated" mode.
=== Widget ===
* The widgets are similar to those in Windows 11, but they can be placed on the home screen.
* News is only visible in the "News" app.
== Development ==
In 2019, Microsoft announced Windows 10X, but senior Microsoft executives were not optimistic about this new variant of the operating system, citing redundancy in features. Therefore, internally in 2020, Microsoft began secretly developing a new system called Windows Sirius. Originally intended to be named Windows 11 Core, the final appearance differed significantly, leading Microsoft to retain the codename with "OS" appended, symbolizing a new system variant.
== Builds ==
=== Windows Sirius build 19561sr(Dev)(2020-02-06) ===
This is the first known version. In the leaked virtual machine file, its appearance is identical to Windows 10X build 19563, except that the wallpaper has been changed to the default Windows 10 wallpaper.
===== Bugs and quirks =====
* Bluetooth and infrared do not work.
* When opening the camera, the system will BSOD regardless of driver support.
* The wallpaper cannot be changed.
=== Windows Sirius build 19630(Dev)(2020-05-14) ===
This version can run Win32 applications. At the top of the desktop, a new widget called "Activity Block" has been added, similar to the search feature in Windows 10.
==== Bugs and quirks ====
* Bluetooth and infrared do not work.
* When using the "Activity Block," the user interface may extend beyond the screen.
* Switching languages while using the keyboard can cause the system to freeze.
* When downloading Win32 applications from the Microsoft Store, the app can open, but it will cause a BSOD after 3 seconds.
=== Windows Sirius build 20174(Dev-1)(2020-07-17) ===
On widescreen displays, the taskbar has been changed to an oval shape. A "Time" widget has been added to the home screen, along with a new default wallpaper.
==== Bugs and quirks ====
* Clicking the "Time" widget defaults to opening the calculator.
* The redesigned taskbar disappears in dark mode.
* Wi-Fi automatically disconnects when the screen is locked.
* Bluetooth cannot pair.
=== Windows Sirius build 20257sr(Dev-2)(2020-11-6) ===
This version has not been leaked. Images show that the "Time" widget now includes the date. A notification bar similar to that in Windows 10 Mobile has been added at the top. At the bottom, "Edge," "Mail," "Phone," and "Microsoft Store" are added by default. The upward-pointing icon has been moved to the center, and the Tab Manager button has been removed.
=== Windows Sirius build 21284(Insider Preview)(2020-12-5) ===
This is the first public preview version. It supports the Android On Windows feature (Windows Subsystem for Android). The wallpaper has been changed to a pre-release style. The search slogan has been updated to "Search the web and your stuff." The default bottom icon has been changed from the original Edge to Edge Dev.
==== Bugs and quirks ====
* Installing Google apps after setting up Android On Windows may cause the Android On Windows mode to fail to start. The only solution is to restore the device to factory settings.
* Restoring factory settings may occasionally result in boot failures.
* Messages may fail to send within the built-in messaging app.
* Activating power saving mode may lead to a BSOD (Blue Screen of Death).
* Connecting a Bluetooth mouse may cause the device to be uncontrollable.
=== Windows Sirius build 21327(Insider Preview)(2021-02-26) ===
The wallpaper has been changed to the final version. The "Time" widget now includes a calendar and weather. The "Activity Block" has been updated with rounded corners, and a Cortana button (changed to Copilot button in 24H2) has been added to the right. On small screens, the Start menu has been completely redesigned, combining the Start menu and the Activity Block. Additionally, File Explorer has been redesigned.
==== Bugs and quirks ====
* The "Time" widget disappears in dark mode.
* Disabling animations prevents the Start menu from displaying.
* Using Cortana in the "Activity Block" causes the system to crash.
=== Windows Sirius build 21380(Pre-RTM)(2021-5-11) ===
Many bugs have been fixed, and five new wallpapers have been added.
==== Bugs and quirks ====
* Edge is unable to access any web pages.
=== Windows Sirius build 21400(RTM)(21H2)(2021-5-12) ===
Officially released. The bug preventing Edge from accessing any web pages has been fixed.
=== Windows Sirius build 22620(Update)(22H2)(2022-8-3) ===
Drag-and-drop support for the taskbar has been re-added. The Start menu now supports creating folder groups. Additionally, the layout of the Start menu can be customized with options for showing more pinned apps or more recommended items. The Focus Assist feature has been split into Focus and Do Not Disturb.
=== Windows Sirius build 22630(Update)(23H2)(2023-9-28) ===
Supports ARM32 applications on ARM64 processors. Copilot has been added.
=== Windows Sirius build 26100(Update)(24H2)(2024-4-5) ===
Copilot's new skills include options to display device information such as Wi-Fi networks, IP addresses, available storage space, and the ability to empty the recycle bin. The new eraser in the Photos app can remove unwanted objects. Windows Ink support has been expanded to applications like Photos, Paint, WhatsApp, and Messenger. The Windows sharing page options have also been extended to include apps such as WhatsApp, Snapchat, and Instagram, with more apps like Facebook Messenger coming soon.
=== Windows Sirius build 27100(Update)(25H2)(2025-6-29) ===
Windows Subsystem for Android now includes Google apps by default (optional installation) and has been upgraded to Android Vanilla Ice Cream (version 15).
== Gallery ==
Desktop(Moblie)
Bootscreen
Edge(Dev)
Default keyboard
Running on Surface Laptop Go 2
The Developer Preview(build 21284) running on the Surface Neo
Copilot
Windows Sirius build 19561
BSOD
File Explorer
Start menu
build 19630 on mobile