Windows 11 build 21996

Windows 11 build 21996 is the earliest available build of Windows 11. This build was leaked on 15 June 2021. Some areas already identify itself as Windows 11, however the kernel version remains the same.

System requirements
This build raises the system requirements when compared to Windows 10:
 * 4 GB of memory
 * Secure Boot support
 * TPM 2.0 support

However, the operating system doesn't actually require any of these to boot, with the requirements being only enforced by setup. It is therefore possible to circumvent them by using  to apply the install image or by using a Windows 10 installer with this build's.

Start menu and Taskbar
This build introduces a new taskbar, similar to the one used by Windows 10X. Unlike previous versions of Windows, the Start button and application buttons are centered by default, rather than aligned to the left, although the old behavior can be reenabled in Settings. The new taskbar also seems to have removed support for custom toolbars such as the Quick Launch panel.

The option to use smaller icons and show window/applications names in the taskbar have been removed. The setting to show the taskbar on all displays was also removed, although it can be toggled directly using a registry value:

News and Interests have also been removed from the new taskbar and replaced Widgets, a panel available from the taskbar that slides from the left and contains weather and news provided by MSN. It is currently unknown if the feature is planned to support third-party content, although the current implementation does not.

Together with the new taskbar, the Start menu has been greatly revamped. Live tiles have been completely removed, with the intended replacement also being the new Widgets panel. The main page shows icons of pinned applications in the top half, with the full list of apps being available by clicking the "All Apps" button in the top right corner. The lower half shows recommended apps and files, which can also be expanded by clicking the "More" button on the right side. The bottom panel contains the power button on the right and the user name and picture on the left, which when clicked reveals links to user account settings, logoff and lock features.

Similarly to the multi-monitor taskbar, the new Start menu can also be disabled using a registry value, reverting back to the Windows 10 design:

General

 * File Explorer received a new icon.

Bugs and quirks

 * On some machines, attempting to upgrade will cause a  bugcheck. Retrying the upgrade may let the user successfully upgrade.