| Software | Status | |----------|--------| | Chrome 120+ | Works (after API shim) | | Firefox 121+ | Works natively | | Steam | Works with manifest edit | | OBS Studio 30+ | Works | | Python 3.12 | Works | | Node.js 20+ | Partial (some crypto APIs missing) | | Office 365 (modern) | Fails – requires Win10 task scheduler APIs |
Take Ownership of System Files
Navigate to C:\Windows\System32. Take ownership of ntoskrnl.exe and ntkrnlmp.exe using tools like TakeOwnershipEx.
Run the Patcher
Most Extended Kernel distributions include an automated patcher (extended_kernel_setup.exe). Run it as Administrator. It will: Windows 8.1 Extended Kernel
Apply Post-Install Tweaks
Reboot
After reboot, check winver – it may still say Windows 8.1, but tools like Get-WmiObject will report kernel version 10.0.19045.
Warning: This is for advanced users. Backup your system first. | Software | Status | |----------|--------| | Chrome
Will the Extended Kernel survive for the next five years? The project has a few existential threats:
As of now, development is active. The release of in development version 1.6 is targeting support for the Windows App SDK (WinUI 3). If that happens, Windows 8.1 will effectively run modern "Windows 11-style" apps. Run the Patcher Most Extended Kernel distributions include
Windows 8.1 reached End of Support on January 10, 2023. This Extended Kernel is a community-driven compatibility layer and system modification that allows modern software – originally requiring Windows 10 or 11 – to run on Windows 8.1.
The Extended Kernel is an unofficial, third-party set of modified system files (primarily ntdll.dll, kernel32.dll, user32.dll, and other core libraries) that backports key APIs from Windows 10/11 to Windows 8.1. In simple terms, it tricks modern software into believing it’s running on a newer OS.