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No that was for CK (Creation Kit) that is a suite of tools for making mods. A new update was released for the game a few hours ago though. If you have kept your manifest (appmanifest_377160.acf) set to read-only (right click->properties), it's easy to fix. For the english version there were only 2 manifest ids that needed to be edited (for the exe and content b). For other languages there might be an additional id to change. Look at SteamDB for the new manifest IDs. The instructions on page 1 are still valid so just follow those. If your game has already updated, switching to GOG might be the best future proof method. Or you can try this.

Another update for CK was posted yesterday. Assuming Steam haven't updated and your (appmanifest_1946160.acf) is still read-only, it shouldn't be difficult to fix. Make sure Steam isn'r running then change to the new Manifest IDs (there's two) as listed in the SteamDB depository here. Don't forget to make the manifest read-only again after changing, before starting Steam again.

The steps on page 1 worked for me. If you can't find the manifest (appmanifest_377160.acf), maybe you have installed it elsewhere on another partition? Once you find the manifest, do the steps on page 1 (while Steam is not running, make sure you choose Exit and not just close the window). Also check (before making the manifest read only) that the following flags matches: "appid" "377160" "name" "Fallout 4" "StateFlags" "4" "UpdateResult" "0" "BytesToDownload" "33393870416" "BytesDownloaded" "33393870416" "BytesToStage" "37409240201" "BytesStaged" "37409240201" "AutoUpdateBehavior" "1" "AllowOtherDownloadsWhileRunning" "0" "ScheduledAutoUpdate" "0" The Bytes fields just need to match it's neighbor.

I think there was a flag in the manifest that indicate if there's an update available. Try setting it back to zero. If you do this while Steam is not running, maybe it will stop? There were also a couple of other fields that kept track on how much it have downladed/have left to download. If they are different, try setting them to the same number. If it managed to update, there probably isn't much you can do unless you have a backup. GOG might be an alternative then for getting the old gen version back.

Well, the instructions worked for me. So far Steam thinks it's up to date but time will tell. I set Steam offline a day before the update arrived, so it never ever thought there was an update. I also made the Manifests read-only. The only issue (if you can call it that) is that the main menu Creation Club news are disabled. A really important thing is probably just that. Set the manifest(s) to read only, and always turn off Auto Updates. I use this method to do that for ALL my Steam games. Dont forget about doing the same for CK if you have it installed (appmanifest_1946160.acf). The SteamDB depository is here.