To get your modded game running on this version, you must match the extender version exactly to your executable's build.
Would you like a that use these SKSE 1.6.640 features? skyrim skse 1.6.640
A critical component for modern SKSE is the Address Library, a database that allows SKSE to find necessary functions without the user needing to manually configure offsets. When 1.6.640 released, existing Address Library files were rendered obsolete. The SKSE team had to generate a new configuration file ( address-library-1.6.640.json ) to allow the extender to communicate with the new binary. Without this, the "hooks" would fail, causing the game to crash immediately upon launch. Report: "Skyrim SKSE 1
: To run mods on this game version, you specifically need SKSE64 build 2.2.1 . How to Check Your Skyrim Version A critical component for modern SKSE is the