Fix "Workshop Item Version Is Different Than Server's" (Zomboid)

The Project Zomboid error "Workshop item version is different than server's" means a Workshop mod updated on Steam and your game downloaded the new version, but the server is still running the old one. The fix is almost always to restart the server so it downloads the update. If it still fails, clear the server's Workshop cache so it re-checks every mod, then have the affected player refresh that one mod.

Quick fix

1. Warn players, then save and quit the server.
2. Start it again. The server checks WorkshopItems on start and downloads updates.
3. Try joining again.
4. Still failing? Stop the server, delete appworkshop_108600.acf in the server's steamapps/workshop folder, and start it again.
5. Still failing for one player? That player unsubscribes from the mod named in the error, restarts Steam, and joins again so the game downloads the current version.

Why it happens

Steam updates Workshop mods on players' PCs automatically, often while they are not even playing. A dedicated server only checks for mod updates when it starts. So when a mod author pushes an update:

• Players get the new version straight away.
• The server keeps the old version until its next restart.
• Anyone joining gets the mismatch error and a kick.

With big mod lists, this can happen several times a week, because one of your 40 mods updates almost every day. The longer a server runs between restarts, the more likely it is.

The message may name the mod ID, or say only that a Workshop item is different. The server log (console.txt in the Zomboid folder) shows which Workshop ID failed.

Fix 1: Restart the server

This fixes most cases on its own. Use quit in the console so the world saves, rather than killing the process. When it starts, the log shows it checking and downloading Workshop items. Once it reports the server has started, try joining.

Fix 2: Force the server to re-check every mod

Sometimes the server believes it already has the latest version. Force a fresh check:

1. Stop the server with quit.
2. Open the server install folder, then steamapps/workshop.
3. Delete appworkshop_108600.acf. This is the file where the server tracks which mod versions it has.
4. Start the server. It goes through every Workshop item and downloads anything outdated.

If that still does not work, delete the whole steamapps/workshop/content/108600 folder instead. The server re-downloads every mod on the next start, which takes longer with big mod lists but clears any corrupted download.

Do not delete your Saves folder or your ini file. Neither has anything to do with this error.

Fix 3: Refresh the mod for one player

If one player keeps failing while everyone else joins fine, their copy is the odd one out:

1. Note the mod from the error or server log.
2. Unsubscribe from that mod on its Workshop page.
3. Fully quit Steam (not just close the window) and start it again.
4. Join the server. Project Zomboid downloads the version the server has.

Avoid unsubscribing from every mod or wiping the whole Workshop cache on the player's PC first. That forces a huge re-download and does not help if the server is the one that is behind.

Fix 4: Check your mod lines

If the error keeps coming back even after restarts, look at servertest.ini (or your server's own ini) with the server stopped:

WorkshopItems=2875848298;3490188370
Mods=ModIdOne;ModIdTwo

• Every mod in Mods should have its Workshop ID in WorkshopItems.
• Remove IDs of mods you no longer use. A removed or hidden Workshop item can break every join.
• Some mods have several Mod IDs in one Workshop item. Only enable the ones you need.
• On Build 42, only use mods marked as Build 42 compatible. Some Build 42 releases expected a backslash before each Mod ID (\ModId), so if mods refuse to load at all, check the format the mod page and server log show for your build.

Stop it happening every day

• Restart on a schedule. A daily restart at a quiet hour keeps the server's mods current. Warn players first with servermsg.
• Use checkModsNeedUpdate. This console command checks whether any Workshop mod has updated and writes the answer to the server log, so you know when a restart is needed.
• Keep the mod list lean. Every extra mod is another chance of an update breaking joins.
• Back up before mod updates. A mod update can also break a save, not just joins.

On a hosted server this is a quick job: hit Restart in the control panel and the server pulls updates on start. With a Project Zomboid server from GamezServers you also get a one click Backup before you restart and a file manager to fix the WorkshopItems line in the browser. The Project Zomboid hosting guide covers mods in more detail.

Other mod errors you might see

• Mod not found or missing mods on join: a Mod ID in Mods is misspelled, or its Workshop ID is missing from WorkshopItems.
• Server crashes on start after adding a mod: the mod does not support your build, or needs another mod as a requirement. Check its Workshop page for "required items".
• Map does not load: map mods need their folder name added at the start of the Map= line, before the base map.

FAQ

Why do I keep getting "workshop item version is different than server's"?

A mod updated after the server last started. Restart the server so it downloads the new version.

Do I need to delete my mods to fix it?

No. Restart the server first. Only delete appworkshop_108600.acf on the server if a restart does not help.

Can players fix this themselves?

Only if they are the odd one out. If the server is behind, only a server restart fixes it.

Will restarting the server lose progress?

Not if you stop it with quit or save first. The world saves before shutdown.