You run a Project Zomboid server and need admin rights, the commands that still work on Build 42, and settings that stay put after you save them. This guide covers all three for 42.21, the stable version since 28 September 2026. Commands and defaults come from the PZwiki pages on admin commands, server settings and the dedicated server, last revised for 42.20, and later changes from The Indie Stone's patch notes and forum. Version 42.22 has been in testing on the new Pre-Release branch since 27 October.
Quick answer: Project Zomboid admin commands work in the server console without a slash and in the game chat with one. To become admin, join your server once and type setaccesslevel "YourName" "admin" in the server console; whoever starts a world with the Host button is admin already. Server rules are in Zomboid/Server/servertest.ini and gameplay settings in servertest_SandboxVars.lua, or in files named after your -servername. When server settings won't save, check the profile name, edit the .lua file with the server stopped, run only one server process, and switch off main menu mods before you create settings under Host.
How to Become Admin on a Project Zomboid Server
Promote your own account. Join once so the server creates your account (with Open=true, the default, that happens at the first login), then type this in the server console with the username you log in with:
setaccesslevel "YourName" "admin"
Use the default admin account. A new dedicated server creates a default admin account on its first start and asks for its password in the console. With the startup parameters -adminusername and -adminpassword you pick the name and password yourself and skip the prompt. Both only act when that account is created:
bash start-server.sh -adminusername YourName -adminpassword 'a-long-password'
On Windows, add them to the java line in StartServer64.bat after zombie.network.GameServer, where the wiki puts -servername. Then connect through Join and Favorites with the server's IP address, port 16261, and that name and password.
Host from the main menu. The 42.21 patch notes made sure "the default role for host connection is set to admin", so whoever hosts is admin.
Roles in Build 42
setaccesslevel takes one of the six levels the wiki lists: user, priority, observer, gm, moderator and admin. Build 42 adds custom roles with their own capabilities, and the system is still settling: 42.14.0 fixed role capabilities lost on a restart, 42.16.0 stopped moderators from granting themselves the admin role, and 42.21 made setaccesslevel and grantadmin work for players who are not on the whitelist. Give admin only to people you would trust with your save.
Project Zomboid Admin Commands for Build 42
In the server console, type the commands as shown; in game, put a slash in front, as in /players. /help lists every command and /help kickuser explains one. Item names are case-sensitive: Base.Axe works, base.axe does not. Syntax and examples follow the wiki's command list, revised for 42.20.2.
Players and moderation
| Command | What it does |
|---|---|
players | Lists everyone online |
kickuser "Name" -r "reason" | Kicks a player; the reason is optional |
banuser "Name" -ip -r "reason" | Bans a player; -ip bans the IP address as well |
unbanuser "Name" | Lifts a ban |
banid SteamID, unbanid SteamID | Bans or unbans a SteamID |
adduser "Name" "Password" | Creates an account on a server with Open=false |
setpassword "Name" "NewPassword" | Sets a new password for an account |
Server, saving and settings
| Command | What it does |
|---|---|
servermsg "Restart in 5 minutes" | Sends a message to everyone |
save | Saves the world |
quit | Saves and stops the server |
showoptions | Lists the server options and their current values |
changeoption PublicName "My Server" | Changes one server option |
reloadoptions | Reloads the .ini and sends it to the players |
checkModsNeedUpdate | Checks for Workshop updates and writes the answer to the log |
Teleports, items and events
| Command | What it does |
|---|---|
teleport "Name" | Takes you to a player |
teleportplayer "Name1" "Name2" | Moves one player to another |
teleportto 10000,11000,0 | Takes you to x,y,z coordinates |
additem "Name" Base.Axe 5 | Gives items; without a name they go to you |
addvehicle "Base.VanAmbulance" "Name" | Spawns a vehicle at a player |
addxp "Name" Woodwork=2 | Adds XP to a skill |
invisible "Name" -true, noclip "Name" -true | Hides a player from zombies, or lets them walk through walls |
createhorde 150 "Name" | Spawns a horde near a player |
startrain 50, stoprain, startstorm 2 | Controls the weather; the storm length is in game hours |
Remote tools use RCON with RCONPort (27015 by default) and a strong RCONPassword from the .ini.
Where the Server Settings Live
A dedicated server keeps its settings in the Zomboid/Server folder of the user that runs it: %USERPROFILE%\Zomboid\Server on Windows, ~/Zomboid/Server on Linux.
| File | What it holds |
|---|---|
servertest.ini | Server rules: name, password, slots, PvP, mods, backups |
servertest_SandboxVars.lua | Gameplay: zombies, loot, time, XP |
servertest_spawnregions.lua, servertest_spawnpoints.lua | Where new characters start |
Zomboid/Saves/Multiplayer/servertest | The world itself |
servertest is the default name; with -servername MyServer the server reads MyServer.ini and the matching .lua files and keeps its own save folder. Edit the files in a text editor or in game under Host and Manage Settings. The .ini can be saved while the server runs and applied with reloadoptions; otherwise the server uses the files at its next start.
Server .ini Settings That Matter
Defaults from the wiki:
| Setting | Default | What it does |
|---|---|---|
PublicName | My PZ Server | Name in the server browser |
Public | false | Lists the server in the in-game browser; Steam's browser shows Steam servers anyway |
Password | empty | Password to join; ignored when you play through Host |
Open | true | New players get an account at first login; with false you create accounts with adduser |
MaxPlayers | 32 | Player slots, admins not counted |
PVP, SafetySystem | true, true | PvP is allowed, but each player switches their own PvP mode on and off |
PauseEmpty | true | Game time stops while nobody is online |
SaveWorldEveryMinutes | 0 | Saves loaded map areas every set number of real minutes; at 0 an area is usually saved when players leave it |
BackupsCount, BackupsOnStart, BackupsOnVersionChange | 5, true, true | Backups at every start and version change, five kept |
SpawnPoint | 0,0,0 | Sends every new player to one x,y,z spot; ignored at 0,0,0 |
DoLuaChecksum | true | Kicks players whose game files differ from the server's |
The wiki caps MaxPlayers at 100 and warns about desync above 32, though the 42.20.3 hotfix added "support for up to 254 players and administrator access when servers are full". DoLuaChecksum can flag false positives on Linux servers, says the wiki; our "File doesn't exist on the client" guide covers that. Spawn coordinates are in our Build 42 map guide.
Mods go on the WorkshopItems=, Mods= and Map= lines. Guides disagree on the Build 42 format of Mods=, so let the game write it, as our mods guide shows. On our Project Zomboid hosting you add Workshop IDs and Mod IDs in the panel and restart; the mods download automatically.
SandboxVars.lua Settings That Matter
Values from the wiki's Build 42 file, which uses numbers where the game menu shows names:
| Setting | Values | What it changes |
|---|---|---|
Zombies | 1 Insane, 2 Very High, 3 High, 4 Normal, 5 Low, 6 None | Population preset; it also sets PopulationMultiplier |
ZombieConfig.PopulationMultiplier | 0.00 to 4.00: Insane 2.5, Very High 1.6, High 1.2, Normal 0.65, Low 0.15 | The population itself |
PopulationStartMultiplier, PopulationPeakMultiplier, PopulationPeakDay | 1.0, 1.5, 28 | Population at the start and at its peak, and the day of the peak |
ZombieRespawn, ZombieConfig.RespawnHours | 4 (None), 0 | Respawn is off by default; RespawnHours at 0 disables it |
ZombieLore.Speed | 1 Sprinters, 2 Fast Shamblers, 3 Shamblers, 4 Random | With Random, SprinterPercentage (0 to 100) sets the share of sprinters |
FoodLootNew, WeaponLootNew and the other ...LootNew lines | 0.00 to 4.00 | Loot per category; food is 0.80 by default, weapons 0.60 |
HoursForLootRespawn | 0 | Above 0, containers in towns refill after that many hours, if they were looted once |
MultiplierConfig.Global | 1.0 | XP rate for every skill while GlobalToggle is true |
DayLength | 4 | One in-game day lasts 1 hour 30 minutes |
WaterShut, ElecShut | 2, 2 | Water stops after 0 to 30 days, power after 14 to 30; 9 disables the shutoff |
Sprinters on multiplayer servers are new: 42.17.0 fixed "being unable to set Zombie speed in MP", and The Indie Stone called the sprinter option for servers "a prototype" when it arrived. On a Space-Node Project Zomboid server you can also set them in the panel, from zombie population and speed to loot rarity and XP multipliers.
Map Reset: A New World With the Same Settings
- Warn everyone with
servermsg, then stop the server withquit. - Copy
Zomboid/Savesto a safe place. - Delete or rename the world folder,
Zomboid/Saves/Multiplayer/servertest(or your server's name). LeaveZomboid/Serveras it is. - Start the server. With no world data, it generates a new world and uses the settings files it finds.
Players' own map of the old world is stored on their PC under the server's IP address and port; the wiki suggests a new port to start it fresh. The -Dsoftreset parameter does not work as of 42.21.0, says the wiki. A Build 41 world can't move to Build 42 at all (B42 checklist); our Build 42 update guide covers the legacy41 branch.
Server Settings Won't Save or the Server Won't Start
Settings that will not save or apply
- The server loads a different profile. It reads the files named after its
-servername, so edits toservertest.inido nothing on a server started asMyServer. - You edited the .lua file while the server ran. The wiki documents a live reload only for the .ini; the .lua files count from the next start. Stop the server with
quit, edit, then start it again. - The setting does nothing in your mode. The wiki marks
PasswordandMaxAccountsPerUseras ignored when you play through Host, andSleepNeededas ignored whileSleepAllowed=false. - Your .ini comes from an older build. 42.18.0 renamed
DisableSafehouseWhenPlayerConnectedtoDisableSafehouseWhenOwnerConnectedand removedAutoCreateUserInWhiteList. Compare old lines with the file your 42.21 server writes. - The population is not what you set.
ZombiessetsPopulationMultiplier, so keep both at the same level. In a Build 42 forum thread, an admin traced odd values to a mismatched pair and found that world generation settings such as the starting population only applied to a new world. - Create New Settings jumps back to the list. In a 42.20 bug report, "Reloading LUA" appears and the game returns to the list. The MP QA team could not reproduce it and named installed mods as a possible cause; two players tied it to mods enabled in the main menu, and one fixed it by switching those off first.
- Progress is gone after a restart. In a 42.20.2 bug report, The Indie Stone's MP QA traced lost progress to
[SQLITE_BUSY] The database file is lockederrors: "Most likely, multiple server instances were running at once", after Start was clicked more than once under Host. 42.21 fixed that. On a dedicated server, make sure the old process has stopped before you start a new one.
A server that won't start
- Not enough memory. StartServer64.bat asks for 16 GB by default, and the wiki says the server fails with memory errors unless you lower
-Xmsand-Xmxto what the machine has. - Java mods after an update. The Indie Stone warned on 21 October 2026 that "Java-based mods will be fundamentally broken by those updates, without warning." Remove them and validate the server files with SteamCMD's
app_update 380870 validate, the wiki's install and update command. - "Assertion Failed: Illegal termination of worker thread". The wiki ties it to an earlier Build 41 server on the same machine:
steam_appid.txtmust hold one line with108600; if that fails, back up your .ini, .lua and save files and remove theZomboidfolder so the server recreates it. - It was started through Steam. The wiki says not to. Verify the files and start it with StartServer64.bat or start-server.sh.
- A hosted world fails after the update. Test it without mods first, as The Indie Stone asks before any bug report. Since 42.21, players on another game version get a notice when they try to connect.
FAQ
How do I become admin in Project Zomboid?
Join the server once, then type setaccesslevel "YourName" "admin" in the server console. Whoever hosts from the main menu is admin already.
I forgot the admin password. Can I reset it?
Yes. Type setpassword "AccountName" "NewPassword" in the server console, which needs no admin login.
How do I ban someone on my Project Zomboid server?
/banuser "Name" -ip -r "reason" bans the account and its IP address, /banid bans a SteamID, and /unbanuser or /unbanid lifts the ban. Run 42.21 or later, which closed a Steam authentication gap that let players get around SteamID bans.
How do I change the zombie spawn rate on my server?
Set Zombies from 1 (Insane) to 6 (None) and keep ZombieConfig.PopulationMultiplier at the matching value; Normal is 0.65. Respawn stays off until you set ZombieRespawn or RespawnHours.
Can I change server settings without a restart?
For the .ini, yes: save it and run reloadoptions, or change one option with changeoption. SandboxVars.lua and the mod lines need a restart.
Can I turn on sprinters on a multiplayer server?
Yes, since 42.17: ZombieLore.Speed = 1 for sprinters only, or 4 (Random) with a SprinterPercentage. The Indie Stone called the option a prototype when it added it.
Sources
All opened on 1 November 2026:
- PZwiki: Admin commands, Server settings, Dedicated server, Startup parameters
- The Indie Stone on Steam: Moving on Up: 42.22 Pre-Release, Build 42.21 Stable Released, Build 42.21 Unstable Released, 42.20.3 Stable Hotfix, Build 42.18.0 Unstable, Build 42.17.0 Unstable, Location, Location, Build 42.16.0 Unstable, Build 42.14.0 Unstable, B42 Checklist, A Note on Java Mods and Modding
- The Indie Stone forums: 42.21 patch notes, B42 MP Server not saving / applying .lua sandbox settings, 42.20.0 Manage server settings fails to create settings, B42.20.2 Hosted multiplayer is not saving data after closing it