Project Zomboid 42.22 Pre-Release: What Changes for Servers
Quick answer: Build 42.22 is out for testing on a new Pre-Release branch since 27 October 2026. Pre-Release replaces the old Unstable branch. Stable stays on 42.21 for now: The Indie Stone keeps each build on Pre-Release for at least a week before it moves to Stable. The headline features are usable ladders and crowbars that force open doors and windows, and the multiplayer fixes include server-side PvP damage, faster server backups and fixes for two dedicated server freezes.
Unstable is now Pre-Release
The Indie Stone renamed its testing branch because "Unstable" confused players, given its long history during Build 42. From now on every update follows the same path: released to Pre-Release, tested for at least a week, then moved to Stable. Urgent hotfixes can still go straight to Stable.
| Steam branch (dedicated server) | Build | Version | Since |
|---|---|---|---|
public (Stable) | 25485538 | 42.21 | 28 September 2026 |
pre-release | 26221949 | 42.22 | 27 October 2026, 12:52 UTC |
42.19 | 24929695 | 42.19.2 | 26 August 2026 |
legacy41 | 24928750 | 41.78.21 | 26 August 2026 |
The unstable branch no longer exists on the dedicated server. A script or panel that still asks Steam for it will not receive 42.22.
What 42.22 adds
- Ladders. The ladders placed around Knox Country are now usable: walk up to one and press E, or use the right-click menu. Zombies cannot climb them. Ladders stay fixed where they are; any you moved earlier keep their new position.
- Crowbars. A crowbar in your hands or inventory can force open locked doors (wood and metal), jammed or locked windows and locked fence gates from the right-click menu. Security doors and jail cell doors cannot be forced. Strength raises the odds, Burglars get a bonus and work more quietly, failed attempts can damage the crowbar, and forcing causes muscle strain.
- Driving. More XXL trees stay visible from the driver's seat.
- Quality of life. You can push with both hands full (the blocking item drops), you cannot sleep with the Bad Smell moodle, and you can open ammo boxes, swap batteries and do several other small actions while walking.
- Animals. Fixes for animals dying when their cell unloads, rabbit kits starving, and chickens disappearing from full hutches.
Multiplayer and server fixes
| Change | Why an admin cares |
|---|---|
| PvP damage is calculated on the server | Fixes hits that were not applied correctly in PvP. |
| Faster server backup creation | The pause during a backup could disrupt play on busy servers. |
| Dedicated server freeze with "Entity is already registered" fixed | A server that hung with this message should stop doing so. |
| Server hang from burning walls next to multi-tile objects fixed | A fire reaching such a wall could stall the whole server. |
| StackOverflowError in ItemContainer.getCharacter() fixed | One less server-side error. |
| Moving vehicles no longer vanish after a reconnect or server restart | A car in motion at a restart could be lost for good. |
| Player-built structures no longer vanish with "Forward Direction cannot be zero length vector" | Bases could disappear without warning. |
| "All Known On Start" map option works in multiplayer | The sandbox setting was ignored on servers. |
| "Zombie Count Before Deletion" sandbox option fixed | It flagged zombies as safe to delete while they were still near a player. |
| Animals no longer deleted from full hutches on server restart | Farms lost animals at restart. |
| Server description keeps its text with special characters | The description could go blank. |
| Character duplication, trailer physics and towing desync fixes, updated anti-cheat | Fewer cloned characters and rubber-banding trailers. |
For mod and map makers, the notes add Town Preview videos for custom maps and move all tile definitions into a tile_definitions subfolder in /media.
Testing 42.22 on a dedicated server
- Back up the server. The Indie Stone says 42.21 saves should not be affected, but recommends a manual backup before you load an existing save on Pre-Release. See restoring backups.
- Switch the server build. With SteamCMD:
app_update 380870 -beta pre-release validate. To return to Stable, runapp_update 380870 -beta public validate. - Move the players too. Client and server versions must match, so a 42.21 client cannot join a 42.22 server. In Steam: right-click Project Zomboid, open Properties, then Game Versions & Betas, and select Pre-Release.
- Check your mods. Mods that touch tiles, maps or crafting are the likeliest to break on a new build. Test on a copy of the world first.
On Supercraft: servers run the Stable build, 42.21, today. A world that has been opened on 42.22 may not load again on 42.21, so keep a backup from before any test.
Read The Indie Stone's 42.22 Pre-Release announcement for the full list.
Running a Build 42 community? Host a Project Zomboid server with Supercraft: daily backups, one-click restores and the server build kept current for you.
Related Project Zomboid Guides
- What to expect on a testing branch
- Playing Build 42 and the testing branch
- Build 42 Stable migration guide
- Dedicated Server Setup
- Restoring backups
Frequently asked questions
What happened to the Project Zomboid Unstable branch?
The Indie Stone replaced it with a new Pre-Release branch on 27 October 2026, starting with Build 42.22. New updates now go to Pre-Release for at least a week before they reach Stable.
When does 42.22 come to Stable?
No date yet. The Indie Stone plans to keep each build on Pre-Release for at least one week and says 42.22 will roll out to Stable soon after testing.
How do I put a dedicated server on the Pre-Release branch?
Run SteamCMD with app_update 380870 -beta pre-release validate. The old -beta unstable no longer exists for the dedicated server.
Can 42.21 players join a 42.22 server?
No. Client and server versions must match, so players need to select Pre-Release under Game Versions & Betas in Steam to join a 42.22 server.
What are the biggest changes in Project Zomboid 42.22?
Usable ladders across Knox Country, crowbars that force open locked doors, windows and gates, server-side PvP damage, faster server backups and fixes for several dedicated server freezes and vanishing vehicles and structures.