How to update your Project Zomboid server

Players can only join a server that runs the same build as their game, and Steam updates their game by itself. Your server installs a new build at its next start when Steam Auto Update is on, which is the default. When it is off, the Game Settings page tells you a newer build is out and offers Update now.

With Steam Auto Update on

1. Restart the server, from the Console or with the ready-made schedule Restart with warnings: How to schedule restarts and backups for your Project Zomboid server.
2. The start checks for a new build and installs it before the game launches. A start after an update takes a few minutes longer. The Console shows the download.

When a newer build is out and Auto Update is on, the Game Settings page shows A newer game build is out: "Steam has build X for your branch, and this server runs build Y. Steam Auto Update is on, so the next restart installs it. Players whose game has updated cannot join until then." Click Restart and update now to do it at once. Nothing restarts by itself.

With Steam Auto Update off

You turn it off to stay on the build you have, for example in the middle of a playthrough when a game update would leave your mods behind. Steam Auto Update is under Show advanced (1) on Game Settings.

1. Open Settings, then Game Settings. At the top, the notice A newer game build is out says which builds are involved.
2. Click Update now. The window Update now? says "The server stops (saving the world), downloads the new build and starts again, which takes a few minutes. Players on it are disconnected. Steam Auto Update stays off."
3. Click Restart and update. The Console shows the download.

If the page says "This server needs a one-time refresh from our team before it can update from here", open a ticket and we will update it for you.

Before you update

• Take a backup: How to back up and restore your Project Zomboid world.
• Check that your mods support the new build, or keep Auto Update off until they do: Project Zomboid mods and Build 42: what to know.
• Tell your players. A world saved by a newer build cannot be opened by an older one.

After you update

Players update their game in Steam, which they usually have already done. If someone still cannot join, they pick the matching branch: Players cannot join your Project Zomboid server after a game update. To hold a specific build, see How to choose Build 41 or Build 42 for your Project Zomboid server.

Mod updates are separate

Game updates and Workshop mod updates both install at a start, but they are different things: How to restart your Project Zomboid server when a mod updates.