If PAYDAY 2 is where I learned this workflow, Skyrim is where most of the internet did. The pattern repeats every year or two: Bethesda ships a small patch — new Creation Club storefront, a crash fix, whatever — the executable changes, and every SKSE plugin compiled against the old binary stops loading. Script-only mods survive; the native-DLL ones that make a 500-mod list actually run do not. The December 2023 patch (1.6.1130) was the worst of these in recent memory — it changed the plugin format itself on top of breaking SKSE — and the current build, 1.6.1170 from January 2024, is where Steam will forcibly keep you.

The community's answer has been the same for years: pin your game to an older executable and stay there — Skyrim is the textbook case of downgrading specifically to keep your mods working, and the general version of that playbook applies to any modded game. Two versions became the standard parking spots, and an entire tooling ecosystem — downgrade patchers, backported compatibility mods, version-specific SKSE archives — exists to keep them livable. Skyrim isn't VAC-secured and this is a single-player game; nothing here touches anti-cheat territory.

011.5.97 or 1.6.640?

Don't pick a version by vibes — pick the one your modlist targets. If you're following a Wabbajack list or a guide, it names its game version on the first page and that decision is made for you. Choosing freely, the trade looks like this:

Version	What it is	Choose it when
1.5.97 (Nov 2019)	The last pre-Anniversary "Special Edition" build. The largest legacy plugin library ever assembled — years of SKSE DLLs that were never ported forward.	Your list is older, or depends on plugins that only exist for 1.5.97. The classic choice; still hugely popular.
1.6.640 (Nov 2022)	The stable mid-Anniversary build, before the 1.6.1130 format change. Most actively maintained modlists target this today.	You want modern mod support and AE content with the least friction. My default recommendation in 2026.
1.6.1170 (current)	What Steam gives you. SKSE itself supports it fine — many individual plugins don't.	Your full list explicitly supports it. Then you don't need this page.

Each version is three manifest IDs — Skyrim splits across three Windows depots (base content, update content, and the executable), and you need all of them from the same version or you'll Frankenstein an install that crashes on the main menu. I learned that the hard way the first time, mixing a 1.5.97 executable with 1.6 content and staring at an instant crash-to-desktop. These are the community-canonical IDs, cross-checked against the long-running Steam guides and SteamDB's manifest history:

Depot	1.5.97	1.6.640
`489831` — base	`7848722008564294070`	`3660787314279169352`
`489832` — update	`8702665189575304780`	`2756691988703496654`
`489833` — exe	`2289561010626853674`	`5291801952219815735`

02Before you touch anything

Saves first Skyrim saves record which plugins they depend on, and saves made on 1.6.1130+ may use the extended plugin range an older engine can't fully load. Copy Documents\My Games\Skyrim Special Edition\ (saves + INIs) somewhere safe, and turn off Steam Cloud for the game while you're version-hopping — a cloud sync against a downgraded install is how progress quietly disappears. Honestly, the cleanest path after a downgrade is a new character; carrying an endgame save backwards across engine versions works more often than not, but "more often than not" is a bad place to keep 300 hours.

One more thing worth doing while the current version is still on disk: copy the whole steamapps\common\Skyrim Special Edition folder to an external drive. Five minutes now, and you can flip between versions forever without asking Steam's servers for anything.

03Downloading the old build

This is a nice showcase of a DepotDownloader feature most guides miss: -depot and -manifest take lists, paired one-for-one, so all three depots come down in a single command. For 1.6.640:

> .\DepotDownloader.exe -app 489830 -depot 489831 489832 489833 \
    -manifest 3660787314279169352 2756691988703496654 5291801952219815735 \
    -username you -remember-password -dir .\skyrim-1.6.640

For 1.5.97, swap in the three IDs from the first table. You must log in with an account that owns Skyrim Special Edition — depot keys are license-checked, so anonymous mode and borrowed builds are off the table. Expect a full reinstall's worth of data, a dozen-plus gigabytes. If you don't have the tool yet: two-minute install.

No DepotDownloader handy? The same three downloads work through Steam's own hidden console — open steam://nav/console in your browser's address bar and feed it download_depot 489830 489831 3660787314279169352 and so on, one depot at a time. It's the method most YouTube tutorials show. The trade-offs: no progress display, no resume, files land in Steam\steamapps\content\app_489830\, and you fish them out manually. It proves the manifests are alive, but for anything you'll do twice the dedicated tool is kinder.

04Installing and locking the version

Merge the three downloaded depot folders into one — copy the contents of each over a single folder, letting files overwrite. (DepotDownloader with -dir as above already gives you one merged folder; the Steam-console route gives you three to combine.)
Copy the result over steamapps\common\Skyrim Special Edition, replacing everything. Verify the downgrade took: right-click SkyrimSE.exe → Properties → Details, or check the version in the game's System menu.
In Steam: game Properties → Updates → "Only update this game when I launch it". Steam doesn't offer "never", so we improvise the rest.
The community's enforcement trick: in steamapps\, find appmanifest_489830.acf, open its file Properties and tick Read-only. Steam can no longer rewrite the manifest, so it can no longer schedule the update. Untick it the day you genuinely want to move forward.
From now on, launch through skse64_loader.exe (next section), never the Steam play button. SKSE launches the game directly, which sidesteps the updater entirely.

05The patcher alternative — when depots are overkill

Fair is fair: for one specific journey — current Steam 1.6.1170 down to 1.5.97 — you don't need to download anything from Valve at all. The Best of Both Worlds Downgrade Patcher on Nexus rewrites SkyrimSE.exe and two DLLs in place using binary delta patches, takes under a minute, keeps backups of both versions, and can even drop in the matching SKSE for you. Because it only touches the executable and leaves the 1.6 game data alone, you keep the Anniversary Edition content while running the 1.5.97 engine — hence the name. It's still maintained (last updated January 2026), Windows-and-Steam only, and it requires your install to be exactly 1.6.1170 before patching.

My honest routing: BOBW patcher if you want 1.5.97 from a current stock install and own AE content; DepotDownloader if you want 1.6.640 (no equivalent patcher journey), need a clean un-Frankensteined install, want a second copy outside Steam, or the patcher's version check refuses your install. The depot route also keeps working when a future Bethesda patch moves the goalposts and the patcher needs weeks to catch up — manifests don't care what version you're coming from.

06After the downgrade: SKSE, Address Library, BEES

The old game needs its old scaffolding — three things, all version-matched:

SKSE64 from skse.silverlock.org — 2.0.20 for 1.5.97, 2.2.3 for 1.6.640 (current builds archive older versions; the files unpack into the game folder, not Data). Your desktop shortcut now points at skse64_loader.exe.
Address Library for SKSE Plugins — the database that lets DLL plugins find their way around a specific executable. It ships in separate editions for the 1.5.x and 1.6.x lines; install the one matching your target or half your plugins will report missing addresses.
Backported Extended ESL Support ("BEES") — Bethesda widened the light-plugin range in 1.6.1130, and newer mods ship plugins older engines can't read. This mod backports that support to 1.5.97 and 1.6.640 and has become a default line in every downgraded load order. Every recent downgrade tutorial — including the video ones — ends with it, with good reason.

And keep mod stacks per version: a plugins folder assembled for 1.6.1170 pointed at a 1.5.97 executable is a crash log generator. Mod managers handle this gracefully with separate profiles.

07Does this still work in 2026?

Yes — and given what happened to old manifests in January 2025, that deserves saying out loud rather than assuming. The manifests in this guide date from 2019 and 2022, exactly the vintage Valve's restrictions hit hardest elsewhere, yet Skyrim's keep answering: community guides reported clean downloads through 2025, and tutorials recorded in 2026 still pull them live on camera. Whether that's deliberate allowlisting or sheer request volume, nobody outside Valve knows. If your download dies with "No manifest request code was returned", that's the Valve-side refusal — here's the full breakdown — and your fallbacks are, in order: the BOBW patcher (doesn't touch manifests at all), the Steam console method with the game's depots, and the status page above for the current weather.

The standing advice stands: the day your modlist works is the day you archive the install folder. Skyrim has outlived four console generations and will outlive these manifests; your external drive is the only update policy you fully control.

Skyrim: the eternal downgrade