Fix common Project Zomboid server errors

Most Project Zomboid server problems come from three places: a mod that changed, a build or port that doesn’t match, or a server that ran out of memory. Find the message you see below and follow the steps. The most common ones are first.

Joining problems

Workshop item version is different than server’s

Why it happens: a mod author published an update on the Steam Workshop. Your game got the new version, but the server still has the old one. The server only downloads mod updates when it starts.

Fix it:

1. Restart the server from Overview.
2. Wait for Console to show SERVER STARTED.
3. Join again.

If one player still gets the error, they should restart Steam so it finishes updating the mod. To make this rarer, add the Daily restart with warnings preset in Schedules.

File doesn’t match the one on the server

Why it happens: a file in the player’s game is different from the server’s copy. Most often the player put a copy of a mod in their own Zomboid/mods folder by hand, and it’s older or newer than the Workshop version.

Fix it:

1. Read the file path in the message. If it points into the player’s own Zomboid/mods folder, delete that copy of the mod.
2. The player restarts the game and joins. The game uses the Workshop version instead.
3. If the path points to the game’s own files, the player verifies the game files in Steam (Properties > Installed Files).

Server failed to respond

Why it happens: the game couldn’t reach the server at that address and port.

Fix it:

1. Check the port. It must be the one on your address card, not 16261.
2. Check the address in the IP box has no port in it, like knoxcounty.play.wilderack.com.
3. Look at Overview. If the server is asleep, joining wakes it, but the game sometimes gives up first. Wait a few seconds and join again, or open your wake link first.
4. If the server is starting, wait until Console shows SERVER STARTED.
5. If it’s stopped, start it. A server someone stopped on purpose doesn’t wake on join.

The game says your version doesn’t match the server

Why it happens: the player and the server are on different builds, like a player on Build 42 and a server on Build 41. It can also happen for a short time after an update, when one side has updated and the other hasn’t.

Fix it:

1. Check which build the server runs under Settings > Server type.
2. For a Build 41 server, players pick the legacy41 branch in Steam. See joining a Build 41 server.
3. For a Build 42 server, players use the default branch, not legacy41 or pre-release.
4. Right after a game update, restart the server so it picks up the new version, and have players restart Steam.

Connection lost while the map loads

Why it happens: the player connected, but the game lost contact while it was loading the map or downloading mods. Big mod lists, a slow connection, or a server that’s short of memory all cause it.

Fix it:

1. Try again. The second join is often quicker because the mods are already downloaded.
2. Look at RAM on Overview. If it’s near your plan’s limit, restart the server, then consider a bigger plan or fewer mods.
3. Check Console for errors while the player joins. A mod error there points to the mod to remove.
4. Players on Wi-Fi can try a cable or move closer to the router.

Players can’t make an account

Why it happens: the server has Open=false, so only players an admin added can join.

Fix it: add them in Console with adduser "Name" "password", or set Open=true in Zomboid/Server/wilderack.ini and restart. See admins, whitelist and bans.

Mod and server problems

Red error counter and Lua errors

Why it happens: a mod hit an error. Project Zomboid shows a red box with a number in the corner of the screen. One or two errors are often harmless. Errors that keep climbing mean a mod is broken, out of date, or clashing with another mod.

Fix it:

1. Open console.txt in your Zomboid folder. The errors there usually name the mod.
2. Check that mod’s Workshop page for an update or for known clashes.
3. Remove the mod in Mods, restart, and test again.
4. On Build 42, make sure the mod says it supports Build 42.

The server crashes and Console shows OutOfMemoryError

Why it happens: the server needed more memory than your plan has. Java stops with java.lang.OutOfMemoryError in the log. Console shows a helper card with a hint when it sees this.

Fix it:

1. Restart the server.
2. Lower the zombie population, or remove mods you don’t need.
3. Move up a plan. See how much RAM you need.

Mods don’t load after you add them

Why it happens: the Mods= and WorkshopItems= lines don’t match, a required mod is missing, or the mod ID is written the wrong way for your build.

Fix it:

1. Install mods from Mods, which keeps both lines in step and adds required mods.
2. If you added mods by hand, check every Workshop number has its mod ID, and the other way round.
3. On Build 42, each mod ID needs a backslash in front, like \ExampleMod. On Build 41, it doesn’t. See adding a mod by hand.
4. Restart the server and watch Console for lines about the mod.

Still stuck?

Download the latest log from Files and send it to support@wilderack.com with what you tried. Real people read every message.