Windows 12 (L)

For other uses, see Windows 12 (disambiguation).
Windows 12  (codenamed Next Valley) is the next major release of Windows after its predecessor Windows 11. It would be the final main release to use the NT Kernel, with Windows 13, its official succesor, and Windows Zinc, which has no successor or pre-determined predecessor, using the Quantum kernel.
== Change list ==
* New desktop, including a unified App Bar at the top of the screen and a customizable widget in the upper-left corner.
* DreamScene is updated and reintroduced as Live Wallpaper. You can get new Live Wallpapers from the Microsoft Store. The OS comes with a live wallpaper that will interact when the user is moving their cursor around it.
* The Setup & Recovery screen gets an overhaul, now boasting Fluent design.
* Reintroduction of desktop widgets instead of having them in the taskbar as seen in Windows 11.
* Further legacy features overhauled or removed from the source code.
** dialer.exe has been replaced by the UWP dialer (uwpdial.exe) overhaul that supports cellular laptops (which are now more popular).
** Non-UWP windows such as the Properties window, Winver and other advanced configuration features are now either integrated with Settings or reworked for better consistency with UWP design.
** Control Panel has been completely removed and replaced by Settings, which is now reworked to have more features and more fluid navigation.
** Legacy features that were removed can be reinstalled via the Microsoft Store.
* The version string for the Windows version in code and as in About Windows makes a jump from 10.0 to 12.0.
* Windows Subsystem for Android gets upgraded to Android 15.0 "Vanilla" from Android 14.4 “Upside Down Cake” and gains Google apps, installed optionally due to privacy.
* Windows Phone apps can now be installed and run as a tribute to Windows Phone via an Easter egg in the command line. Later they added support to mirror to a Samsung (One UI 4 and later) device.
* Copilot is deeply integrated with the operating system. It can now access content from apps and the user's files, and allows Copilot+ features to be used on non-ARM PCs via Microsoft cloud servers. The AI also allows for voice control similar to how Cortana worked in early versions of Windows 10, and can perform tasks such as adjusting settings, changing the wallpaper, and powering off the system.
* The taskbar is now floating and bears resemblance to the MacOS dock.
== Development ==
Microsoft announced that a newer major version of Windows would come after Windows 11 after the support for the RTM version 21H2; said version would be both free upgrade and capable of fresh installation like Windows 11. The first versions would be available to be tested via the Windows Insider Program as an upgrade from Windows 11 if the device was compatible. Development likely began in early 2022, perhaps involving the Copper builds of Windows 11.
== List of known builds ==
=== Build 260212.1000 (2023-11-02) ===
This build accidentally got unveiled during the 7 first seconds of the Ignite 2023 conference due to the host still being on the desktop. Due to it’s earliness it still identifies as Windows 11 but it’s interface is very similar to Windows 12 final release.
=== Build 261212.1000 (2025-03-11) ===
After a 1-year delay, the first public build for Windows Insiders would be announced in the Windows Insider blog page, announcing Windows 12 and what it could become in the future. This became the earliest build of the Insider program. It is the first build to idenifiy as Windows 12.
=== Build 24800.1000 (2025-04-15) ===
Minor release. Correction of major bugs regarding latency issues on games and productivity applications, and other issues on older processors that were prior to 2018 CPU releases.
=== Build 24810.1000 (2025-04-26) ===
Overhauled WinPE and recovery UI based from Fluent design language seen on Windows 12. Further optimization was made for older devices to run animated wallpapers in the background without disturbing gaming/application performance.
=== Build 24815.1 (2024-05-12) ===
This is the last build that has old dialer app. This build is unstable and will crash on startup, and you can only install it from WinPE. On the first boot after the OOBE, opening the Start menu will cause Explorer to crash.
=== Build 24815.2 (2025-05-13) ===
This build was first sent to insiders as a WinPE image at first. 2 hours later, an update to the build that was a full Windows 12 installation was available. A Windows 12 disk image was shared 5 hours later. Opening the new Phone app or the UWP About Windows App causes an unhandled exception that crashes the OS.
=== Build 24820.50 (2025-08-26) ===
Windows 12 is publicly announced. Beta Channel insiders are now able to test a build that will receive cumulative updates until general availability. The build includes the major features mentioned above and major optimizations with newer and slightly older devices.
=== Build 24820.75 (2025-09-01) ===
Cumulative update with minor fixes for Windows 12.
=== Build 24820.140 (2025-09-10) ===
Cumulative update with minor fixes for Windows 12. This would include major things seen from the Dev builds too and more.
=== Build 24820.200 (2025-09-28) ===
General Availability build of Windows 12. Computers manufactured from the date onwards would come preinstalled with this operating system.
=== Build 25060.2 (2026-07-26) ===
Added support for Emergency Alert System notifications as normal system notifications that will also show when Do Not Disturb is on or the system is in Sleep Mode. Clicking on it displays the full text and metadata.
=== Build 25065.1 (2027-06-27) ===
Another small update, with minor fixes for Windows 12. The Emergency Alert System has a new notification sound, the critical sound alert that pops up in a full window.
Category:Fictional Windows versions