Project Zomboid server not working?
Start here.
Project Zomboid takes bad configuration without a word: the server is unlisted by default, a Workshop ID in the mod-ID box loads nothing, and a Build 41 key on a Build 42 server is ignored with no error anywhere. Most fixes are one field on the Settings tab.
# what fixes most Project Zomboid problems 1 Not in the server browser → Settings → List in Public Browser 2 Workshop mods don’t load → Workshop IDs ≠ Mod IDs 3 Need admin in game → Join as admin + the Admin password
My server isn’t in the in-game browser, or friends can’t get in
It is unlisted by default
Settings → List in Public Browser is off out of the box — the game’s own default. Turn it on and Apply & restart to appear in the in-game public browser.
Or connect by address
Copy the address at the top of the panel and use the game’s direct connect, with the Join Password if you set one. No listing needed.
Open, or whitelist only
Open (no whitelist) is on by default: anyone with the password gets in. Turn it off and only whitelisted accounts can join — accounts, the whitelist and bans live in the game’s own database (pz/db/servertest.db), and the panel has no whitelist editor.
Full server?
Max Players defaults to 32 and does not count admins, so an admin can always get in. The game itself warns that more than 32 risks poor map streaming and desync.
I added Workshop mods and nothing loads
Two boxes, two kinds of id
Settings → RCON, Admin & Mods. Workshop Items takes the Steam Workshop file IDs the server downloads. Mods takes the mod IDs it loads. A Workshop number in the Mods box loads nothing.
Line the lists up
Each Workshop item maps to one or more mod IDs, and both lists — semicolon-separated — have to agree. One Workshop item can carry several mods: list the IDs of the ones you want.
Map mods take a third entry
A map mod also goes in Map, with its own name ahead of the base map: ModMapName;Muldraugh, KY.
Restart
Both lists are written into servertest.ini on every start, so Apply & restart.
Why: PZ has no mod loader to install — the Mods tab only points you back here. The server subscribes to Workshop items, then loads mods by name, so the two lists do different jobs.
How do I get admin in game?
Join as admin
Connect with the username admin and the Admin password from the Settings tab — we generate one per server. It is applied on every start, so a change lands at the next restart.
Promote your own character from there
Use the game’s own admin commands from that account; our Project Zomboid admin commands page lists them. The panel console on this game runs its listed commands only, not whatever you type.
Ban and unban by username
Ban takes a username, not a Steam id — the Players tab lists who is on by username, the handle it takes. PZ does not check the name first: a typo answers System banned user exactly like a success. Unban takes the same name.
Access is the panel, not the game
The Access tab lets a friend into this panel. It does not make them admin in game.
My setting didn’t take, or does nothing
Change it in Settings, then restart
servertest.ini and servertest_SandboxVars.lua are both written from the panel on every start. A change lands at the next restart: Apply & restart.
Hand edits to panel keys get overwritten
In Files, an edit to a key the panel manages is replaced at the next start; a key the panel doesn’t show is left alone. A key the game itself doesn’t know is deleted by the game when it starts.
Build 41 keys do nothing on Build 42
Our servers run Build 42. B41 names like FoodLoot became FoodLootNew (a multiplier now), XpMultiplier is gone in favour of a per-skill table, and PZ ignores an unknown key with no error anywhere. MapRemotePlayerVisibility moved too: a B41 Everyone (3) means friends and nearby players on B42.
Bring an old config in
Settings → Already have a config? Paste or upload it → paste your old servertest.ini → Fill the fields. It fills what it recognises and lists what it doesn’t, so a stale B41 key shows up instead of vanishing.
Why: PZ rewrites both files at startup and backfills every key it knows, so a partial file is fine and a foreign key does not survive. The panel writes its own keys into whatever the game left, which is why a key it doesn’t manage keeps your edit.
Players get kicked: “file doesn’t match the one on the server”
Ask the server which mods are stale
Run Check whether any Workshop mod needs updating on the Console. The answer lands in the server log (on the Console) and in in-game chat, not in the command’s reply.
Restart cleanly
Restart at the top of the panel. The server reads its Workshop list at boot, and the world is saved on the way down.
Last resort: Enforce Lua Checksum
Settings → Enforce Lua Checksum (on by default) kicks clients whose game or mod files don’t match the server’s. Switching it off is the blunt fix people reach for — and it also switches off the check.
Did my world save? We lost progress after a restart
A normal stop saves
Stop, Restart and scheduled restarts send the game its shutdown signal, and it writes the world before it exits — 8.5 seconds on a fresh world, longer on a built-up one. We start the game directly rather than through its own launcher, which kills it mid-save and reports success.
Never Force stop a healthy server
Force stop cuts the power with no save. It is there for a server that will not stop any other way.
Save more often
Settings → Save World Every (min) defaults to 0: areas save only when players leave them, so a crash can take everything since. Set a number of minutes. Save world now on the Console saves on demand.
Roll back
Worlds & backups holds three nightly restore points plus a copy from before your last game update, and every backup forces a save first. Press Restore on the one you want.
Players can’t claim a safehouse
Switch it on
Settings → Player Safehouses is off by default, and so is Admin Safehouses; with both off nothing can be claimed. Apply & restart.
Spawn buildings never qualify
A building that holds a spawn point is refused before any other check.
It has to be a house
Every room must be a house room — bedroom, kitchen, bathroom, living room, garage and the like — and at least one must be a bedroom or living room. The names are exact, so a room the map calls garagestorage, attic or shed fails it. Claim Non-Residential skips this test.
Then the server’s own rules
Days Survived To Claim, the player standing inside with nobody else, no overlapping claim, and no war running.
Why: That is the game’s own claim test, read out of the Build 42.21 code rather than taken from a wiki.
The memory bar says I’m nearly out of RAM
The bar counts page cache
The panel’s MEMORY USED is Docker’s figure, and it includes cache: it read 5.5 GiB for an empty PZ server really using 1.3 GB. Near the cap is not, on its own, a server under pressure.
What we have measured
An empty Muldraugh world: 1.30 GB of real memory. With players on, we have not measured it yet — which is why the plan starts at 4 GB and not 2.
Watch the player count
The game ships its own warning that more than 32 players risks poor map streaming and desync. Settings → Max Players.
If the game itself is struggling
Adjust RAM at the top of the panel moves RAM from your plan to this server. Java’s heap is sized at 70% of whatever the server has, so it grows with it at the next start.
None of these, or still stuck?
Check the problems every game shares
Connections, settings that will not take, where your world is, lag: the answers that hold on every game are on the support page.
Write to us
The form arrives with Project Zomboid already set; tell us what you tried and it saves a round trip. Pressing Need help? in your panel does the same and attaches your server, so there is nothing to look up.