Skyrim Update 1.6.640

Skyrim version 1.6.640 (released September 20, 2022) is widely considered the most stable "Gold Standard" for modding the Anniversary Edition. Because later updates (like 1.6.1130+) broke many popular script-based mods, many players choose to stay on or downgrade to 1.6.640.  Core Components of 1.6.640 

The primary goal of 1.6.640 was to stabilize the game after the 1.6.629 update caused significant technical hurdles. The official fixes included: skyrim update 1.6.640

In the deepest part of the update’s ripple, behind a waterfall near the old ruin of Nchuand-Zel, stood an unmarked door that had never existed the day before. It opened onto a corridor lined with mirrors that did not show faces but decisions: turning left presented a life of comfort, turning right offered hardship and great song. A wandering bard, curious and untethered, walked inside and emerged with a new melody he could not remember composing—but everyone who heard it wept in the same place and laughed in the same breath. Skyrim version 1

...all ceased to function. These mods are hard-coded to look for a specific version of the game’s executable. Since 1.6.640 changed the version number from the previous 1.6.353 (and 1.6.629), any mod not explicitly recompiled for .640 would cause the game to crash on launch. What it does: It keeps your game flagged as 1

• What it does: It keeps your game flagged as 1.6.640 (so Steam doesn't redownload files), but rolls back the SkyrimSE.exe to 1.5.97.
• Result: You get the new Creation Club content (Fishing, Saints, Survival) with the stability and SKSE plugin compatibility of the old engine.

. Players who do not heavily mod their game should allow the game to update to the latest version via Steam to receive all fixes.