The term "Extended Kernel" refers to a set of modified system files (DLLs) that replace or augment the original Windows kernel components. In practice, these projects work by adding stub functions, API exports, and version spoofing tricks to fool modern software into thinking it is running on a newer version of Windows. The most prominent figure in this space is a developer known as (also associated with the Supermium browser and Second System projects), who initially created an Extended Kernel for Windows Vista and later worked on extending Windows 8 and 8.1.
Last updated: April 2026 – The project remains community-driven with no affiliation to Microsoft. Windows 8.1 Extended Kernel