Steam Community :: Guide :: Dedicated Server Steam Workshop Issue (2025)

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Dedicated Server Steam Workshop Issue (2025)

By H U N ナ E R

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H U N ナ E R
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Category: Workshop

Languages: English

Posted

Updated

4 Aug @ 11:30pm

7 Aug @ 3:39am

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Guide Index

Overview

About the problem

Troubleshooting

Comments

About the problem

Currently, there is a problem with updating new workshop items on the KF2 server side. More specifically, all mods (maps, packs, and mutators) that have been compiled/created since 11 July 2025 will no longer be updated on the server. This behavior is not observed on the client side.

Summary

Around February 2025 or before, Steam has added support for ZSTD compression, a faster and more efficient compression algorithm, to improve game download speeds. This new compression method will be used for downloading game files, replacing the previous LZMA compression for certain data chunks.
The latest Steam DLLs from SteamCMD appear to be version 9.86.62.31 from 27 June 2025, and are confirmed working with new workshop items (presumably supporting those new ZSTD compressed chunks).
On 11 July 2025, Steam workshop presumably started saving new content as ZSTD compressed chunks.
Killing Floor 2 dedicated server ships old Steam DLLs, which appear too old to support the new chunks format, and so started failing when downloading them.

Troubleshooting

TWI needs to make a new dedicated server release with updated Steam DLLs. But we don't know when that will happen. Therefore, I am providing a temporary solution to this problem.

Short-term solution (Windows Platform)

Launch SteamCMD to get the latest updates.
Copy the following DLL files from the SteamCMD directory, which are required for updating the server side:
- steamclient.dll
- steamclient64.dll
- tier0_s.dll
- tier0_s64.dll
- vstdlib_s.dll
- vstdlib_s64.dll
Place the copied DLL files in the Binaries\Win64 directory of your server and confirm the replacement.

Short-term solution (Linux Platform)

I am not currently using Linux and cannot find a solution for this platform on my own. But you can use the following solution if it helps:

Launch SteamCMD to get the latest updates.
Copy the following SO files from the linux32 and linux64 of SteamCMD directory, which are required for updating the server side:
- crashhandler.so (linux32 dir)
- libtier0_s.so (linux32 dir)
- steamclient.so (linux64 dir)
Place the copied SO files in the Binaries\Win64\lib64 directory of your server. Beforehand, you can rename the old files to so.old if you need them.

6 Comments

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∀ℳΞ¡ƧΞɲþɘɼ 23 Aug @ 1:28am

From Forrest Mark X [author from UnofficialKFpatch ]
Okay so for the people getting a version mismatch you can download this

https://www.dropbox.com/scl/fi/gedfa3zihsa1xtx888wt3/UKFP_EGS_Old.7z?rlkey=slm8xk97db3il3c2sn9uxjif1&dl=0

This is the version before this update and the one most servers who don't apply the workshop fix will be using.

You install this to Documents\My Games\KillingFloor2\KFGame\Published\BrewedPC

Fair warning that this might cause issues if you join a server using the latest version but it's unlikely if you install it there

ZyrkΔven 22 Aug @ 12:54pm

Hello everyone! I’m having some trouble with UnofficialKFpatch. I can’t join the servers I used to play on, and I’m not sure how to fix it. Could anyone help me or point me to someone who can solve this on my computer? Thank you so much in advance!

cOOKie MoN$TeR 20 Aug @ 12:26pm

Thanks for posting this. New Linux fix works.

H U N ナ E R [author] 7 Aug @ 3:46am

The guide has been updated with a short-term solution for the Linux platform.

H U N ナ E R [author] 5 Aug @ 12:55am

@Kill Master, Yeah, it seems that now in KF2 we are responsible for the maintenance of our servers.But I feel sorry for those people who don't even realize what's going on and why they can no longer play because of it. These developers love their games so much, even more than we do. But they breathe new life into their games not with updates, but with a new number in the game title

Kill Master 5 Aug @ 12:08am

This isn't all too surprising considering KF2's EoL status.

KF1 server operators have been doing the same thing for years, by that I mean replacing the out of date binaries with up to date ones from Steam CMD .
Fail to do so and you're server will fail to even show up on the server list.

The simplest way I've found to do this is to set up a Cron job to run nightly that simply involves copying the prescribed binaries from the Steam CMD directory and overwriting the ones in the server directory.

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