Disclaimer: you must own a legal PC copy of the game to use this patch, it does not contain any original game file and is thus useless without them.
How the patches work
The patches do not contain the entire old files, instead they contain only data about the differences between the old and new files versions. This data is used to transform the newer files back into their old version.
The advantages of this method are a considerably reduced file size and a smaller risk of DMCA takedown.
Instructions
How to use
1. Extract all files to Fallout 4's directory (where Fallout4.exe is located)
2. Run patch.bat and follow its instructions (do not close while patching!!)
3. If you don't play the English version, install string files: click here
4. (optional) Keep a copy of the folder in case Steam updates your game. If you don't do this you will have to wait for a new downgrade patch when a new Fallout 4 update is released.
Notes
-If the .bat seems blocked, right click anywhere inside the window. For some reason selecting text pauses the script on Windows 10, right click to deselect.
-You might need to launch patch.bat as admin if the game is in Program Files.
-You can delete the files you extracted and the .bak files after patching successfully.
-If you closed the window while it was patching and now have corrupted files, you can restore them by renaming the .bak files. Verifying the game cache in Steam is also an option.
-If you want to update to the latest version just verify the game cache in Steam.
Compatibility
-DLCs won't work with versions older than them and are not downgraded along the main game, this might cause unexpected side effects.
-Only the English version is fully supported
Video tutorials (by Petite Miku)
Installation:
Keeping multiple versions of the game:
Troubleshooting
Consistent crash on new game or save loading:
• https://steamcommunity.com/app/377160/discussions/0/364040961444591813
• Delete the .ini files in Documents\My Games\Fallout4
Upon launching the game: "That app can't run on your PC. To find a version for your PC, check with the software publisher":
Files are corrupted, verify the game cache and try to downgrade again.
Instant crash on a non-English version:
Install the string files pack: click here
Downgrade patches
You can check your version number in the game settings.
Downgrade to v1.1.30 (for speedrunning):
1.9.4 -> 1.1.30
Download links: MegaMediaFire
v1.1.30 Backup (not a patch)
If there is no downgrade patch available for a newer version, you can download this partial v1.1.30 backup instead. It contains the files changed by the updates listed below, keep in mind a new update could have changed a file that is not in the backup.
Download links: Mega
Downgrade to any other old version:
To downgrade to any other version than 1.1.30, you will have to go through all the patches in between your version and the version you want.
Download folders: MegaMediaFire
String files
String files must be installed manually for v1.6 and older because they disappeared since v1.7
English string files are already included in the downgrade patches.
v1.1.30 string files pack (English, French, German, Italian, Polish, Portuguese, Russian, Spanish)
Download links: MegaMediaFire
English string files for all versions
Download: Mega
Extra
My Mega folder also contains the scripts I wrote to make patches and game files checksums. Checksums can be verified with HashCheck.
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