Automatic downgrade to 4 earlier versions (Mulderland's Universal Downgrader)

An easy, automated way to downgrade your current Steam version to 4 previous versions. This downgrader is compatible with all languages and doesn't require Steam credentials.

Intro

In August 2026, Skyrim SE was updated once again, this time to version 1.7.99.

Updating a game is generally a good thing, but the problem is that every update can break mods and existing installations.

And while Bethesda could simply add a “beta branch” to the game’s properties, allowing mod users to easily choose which version they want to run, they just don’t seem to care...

So, just like I did for Fallout 4, I decided to create an easy and automatic way to downgrade your Skyrim SE installation.

Key features of this downgrader

This downgrader is called the "Mulderland's Universal Downgrader."

It works exclusively with the latest Steam version of the game (currently v1.7.104) and will be updated quickly whenever a new game update is released.

It can downgrade the game to 4 previous versions :

• v1.5.97, released in November 2019. An old version that I only recommend if you use an old modlist.
  
• v1.6.640, released in September 2022. A version still useful for multiple modlist.
  
• v1.6.1170, released in January 2024. This is the version immediately before the August 20, 2026 updaten and probably the version you want if the latest update has broken your installation.
  
• v1.7.97, release in August 20, 2026. (The version just before the hotfix of August 27, 2026)

Unlike other downgrader, and like my Fallout 4 downgrader, this one

• works with all games languages
  
• doesn't require your Steam credentials
  
• behaves like a "team machine", making it very similar to manually downloading each depot in the steam console, except that the entire process is fully automated.

How To

It's very easy.

1) Get the latest installer

You can find it on my website:
https://www.mulderland.com/games/the-elder-scrolls-5-skyrim-special-edition
Click "Download".

Important: always use the latest installer, as I often rebuild them / add mirrors / change servers.

2) Run

Run the executable (no admin privileges required)
If you encounter any problems, check my help page: https://www.mulderland.com/help

- Now, you should see the welcome screen:

- Here click on the button and browse to your game directory, select SkyrimSE.exe

- The installer will check if your version is compatible:

WARNING: if your game language is English or Chinese, you will have an additional modal, as the installer can't decide which language you have.

In all cases, the installer will ask you to confirm the detected language.

- Then, the component screen, you can choose which version you want to downgrade to:

You can also block future update if you want :)

Click next, wait a couple of minutes and it's done.

---

New screen in 26.08.12:

You may see that during the install, if you have a "ContentCatalog.txt" file in "%LOCALAPPDATA%\Skyrim Special Edition" that in the v1.7.99 format.
It is recommended to say Yes to avoid crashes.

Instead of deleting the file, the installer will rename it to "ContentCatalog.bak", just in case you need it one day.

FAQ & Troubleshoot

The downgrader refuses to run

This might be related to the Mark of the Web or the self-signed certificate.
Visit https://www.mulderland.com/help for more details.

I have a "disk write error" after using "Block future Steam updates"

If you check this checkbox, it will mark the file "appmanifest_377160.acf" as read-only.

This prevents Steam from making changes to your installation (which is what we want), but not in all situations. For example, you may want to:

• Install a DLC that is currently not installed
  
• Change the game language
  
• Return to the current version of the game

To revert the effect of this checkbox :

• Locate the "appmanifest_489830.acf" file.
  
• Right click on the file > properties > uncheck "readonly" > OK.
  
• Finally, click Retry in Steam.

Tip: folder starting with a dot are invisible, but if you type their name in the input, then press Enter, you will enter it.

How to go back to the latest version ?

- If you block steam update, see previous point
- Then, just use the "steam integrity check" feature.

How to use it on Steam Deck or Linux ?

It works on Steam Deck/Linux too. I don't know the exact steps since I don't own a Steam Deck, but you can try launching the installer .exe with Wine or ProtonTricks.

New versions of my installers/downgraders should now automatically detect your game folder, even on Linux/Steam Deck.

The only exception is if your game is installed on an external SD card or drive. In that case, the installer should still point you in the right direction (for example, Z:\run\media\deck).

How this downgrader was made?

- The installer is open source and built directly through GitHub Actions. On my website, you can access the source code. You can even build the installer yourself if you want (see the README in my github repository).
- The xdelta files were created using PowerShell scripts that I've shared here: https://github.com/mulderf0x/fallout-4-downgrader-maker
- I do, however, use a self-signed certificate for the installer (a real one is quite expensive), so false positives can sometimes occur. If you don't trust me, you can scan it with VirusTotal and you'll see that the result is 0 or close to 0. As mentioned previously, you can also compile it yourself.

Thanks

Thanks for reading this guide!

If it helped you, please consider leaving a rating! 😊

You could even buy me a coffee at https://ko-fi.com/mulderland if you like my work.
I’d really appreciate it!

[Visari]

Absolute hero.

[ZeusyPoo]

I will also give you a blowjob

[Granto]

if you ever need a blowjob hit me up

[SlaAps]

i have no more time to play but still have a modded incredible version ready to play installed... so thank you in advance!

god bless you

[solitaire45]

Dear God thank you, gonna have to try this because I assume everything just broke on linux. On windows I just had to change the app manifest

[CanisAbel]

Thank you sooo much man, my mods are saved <3

[Gorty]

Works fine on linux Nobara

[PurpleFlame]

Thank you! I used this downgrader on my Steam Deck, so wanted to post my experience.

I used ProtonTricks to open the .exe application. Click on the downgrader .exe file and select "Open with Protontricks Launcher". ProtonTricks will ask you what game to open; select Skyrim SE. The Mulderland's Universal Downgrader should open, and it worked perfectly fine for me.

When launching my game post-downgrade, I was warned that SKSE was not detected. The game itself was running fine and all the mods were working. However, I could not access the mod configuration inside the menu settings, and there were some visual glitches with the inventory (SkyUI & Dear Diary). To remedy this, I opened Vortex to allow it to deploy the mods. Then I re-ran the Pikdum's Vortex SkyrimSE Post-Deployment script. This seemed to fix the error with SKSE not being detected, despite being installed.

Hopefully this helps, please let me know if anyone has any questions! :)

[zdaszkiemniema]

You are the best! I'm wondering though, if I uninstall Skyrim, will the files from your downgrade be deleted too?

[Scott Dark]

Holy ♥♥♥♥ bro life saver I thought I had set it to read only like 2 years ago but for some reason it auto updated randomly? ♥♥♥♥♥♥♥ legend