Contents
SERVER SETTINGS
Project Zomboid servers allow you to choose between the latest stable version (Build 42) and the legacy version Build 41. You can switch between them simply by entering values in the game panel and reinstalling. Please note the important considerations regarding world handling, which are explained below.
Revision History
- v1.0
- October 2026 — Initial version created
Selectable Versions
Specify in[SYSTEM] Game Version (Steam Branch) on the Startup tab.| Value to Enter | Version | ゲームの版 (Game version) in Console |
|---|---|---|
| Leave blank | Latest stable version (Build 42). Recommended / Default | public |
legacy41 | Build 41 (legacy version) | legacy41 |
Worlds played in Build 42 cannot be opened in Build 41. When switching versions, please use separate worlds (this will be explained in the procedure).
Switching to Build 41
- Press Stop in the Console tab and wait until it stops.
- Take a backup in the Backups tab (backing up after stopping will capture your progress up to the last point you played).
- Enter
legacy41in the[SYSTEM] Game Version (Steam Branch)field on the Startup tab. - Change the
[WORLD] Save Nameon the same tab to a new name (e.g.,World41. Alphanumeric characters,_, and-only).
Worlds played on Build 42 cannot be opened in Build 41, so you will start with a separate world for Build 41. Your original world will not be deleted. - Execute "Reinstall Server" in the Settings tab. Always switch versions by reinstalling.
- Once reinstallation is complete, start the server and verify that the
ゲームの版(Game version) in the console showslegacy41.
Reverting to Build 42
- On the Console tab, click Stop and wait until it stops.
- On the Backups tab, create a backup.
- On the Startup tab, leave
[SYSTEM] Game Version (Steam Branch)blank. - Change
[WORLD] Save Nameback to the name of the world you were playing on Build 42. - On the Settings tab, execute "Reinstall Server".
- Start the server and verify that
ゲームの版(Game version) in the console showspublic.
Players Must Use the Same Version
When you change the server version, all players joining must also match their game to the same version.In Steam's library, right-click Project Zomboid → Properties → select the same version in the version selection screen (Game Versions & Betas in English).Players cannot join if versions do not match. When changing the server to Build 41, make sure to notify everyone you play with.
Important Notes
World Compatibility
If you try to open a world that was played on Build 42 with Build 41, the server will stop during startup. The console will display the following:The server savefile appears to be from a newer version of the game and cannot be loaded.
In this case, change [WORLD] Save Name to a new name or revert to Build 42.
