Simple Fallout 4 Downgrader (Updated)
A simple one-click downgrade feature that does not require any login credentials.
About this mod Machine translation
A simple one-click downgrade feature that does not require any login credentials.
Original address:
Updated on June 24, 2026 with the latest downgrader adapted to version v1.11.221
Updated on December 23rd with the latest downgrader adapted to version v1.11.191
This downgrade software uses delta patches to restore the game executables (main EXE and launcher) to 1.10.163 and restore the Steam API DLL to the pre-update version. It doesn't connect to your Steam account and doesn't require multiple console commands.
Prerequisites
The latest version of "Fallout 4" on Steam (piracy is not supported, and the GOG version is not affected by this update),
F4SE version 0.6.23,
Plug-in library - integrated,
Fallback Archive2 support system, which requires valid archive invalidation (handled by MO2 and Vortex, BethINI Pie's recommended tweak also does this).
instruct
Download the file and extract its contents to the game root folder,
Double-click the downgrade program executable file to start.
Wait for the "Patch successfully" prompt that just opened the console window, and then close it.
Make sure you have the three mods listed in the requirements above.
File backup is also provided in the same folder. Simply delete the new executable and Steam API DLL and remove _downgradeBackup from the backup file name.
Possible problems
**Invalid hash value**
Only the latest versions of Steam games are supported. Piracy is not supported and will get you banned. GOG doesn't need this downgrader because it hasn't been updated in the first place. If you're on Steam and this still doesn't work, verify your game files and try again.
**Game crashes before loading**
Read the prerequisites above and make sure you have the correct F4SE version (0.6.23). Don't forget to run the game through F4SE and your manager.
**NO MAIN MENU BUTTON**
You did not activate the archive. Make sure it's enabled by your mod manager and/or has BethINI Pie's recommended tweaks applied.
**Creation Kit will not open after downgrading**
Downgrading CK also downgrades, or reverts to the original Steam API DLL if CK is required. Root Builder is an easy way to switch between 2 as you can set up CK itself + the original Steam DLL as a mod.
You can follow The Midnight Ride for more restorations and information on mods.
Midnight Ride
grateful
Nukem provides information about the files to be downgraded, as well as BASS.
Description of Ungeziefi.
Install & use Install: follow the bundled instructions
- Unzip the archive from playbuff and read the bundled readme / instructions first.
- There is no universal mod manager for this game: some mods replace game files directly, some go into a game-specific Mods folder, and some need a game-specific community loader or tool first — follow the bundled readme.
- Place the files exactly as the readme says; mods with listed dependencies need those installed too.
- Launch the game to confirm it loaded; some games require enabling mods in settings or an in-game mod menu.
Install locations vary a lot between games and mods — the bundled readme is the most reliable guide.