Project Zomboid B41 vs B42: Squad Up Without Becoming Zombie Chow
TL;DR: To join a server on Build 41, use the in-game Join menu, pick a public server or enter your friend's IP, and make sure your game version and mods match the server. To try Build 42, you'll need to opt into the beta (through Steam) โ but note that official multiplayer is disabled in Build 42. (In a hurry? Skip to the Quick-Start for step-by-step instructions!)
๐ Quick-Start: Joining a B41 Multiplayer Server
Build 41 is the current stable version of Project Zomboid, and it's where all the zombie-slaying multiplayer action is happening. If you and your friends are on Build 41, follow these quick steps to get everyone playing together:
By default, Project Zomboid installs the stable Build 41. Just launch the game normally (no beta selection needed) and check the lower-right corner of the main menu for the version number (should read something like 41.78.x). If it's Build 41, you're good to go.
From the main menu, click on "Join". This opens the Server Browser interface where you can find servers or connect directly.
To join a public server, go to the Internet tab in the Join menu. Here you'll see a list of servers currently running Build 41. Use the filters at the bottom (search by name, player count, etc.) to narrow it down. For example, type part of the server's name or select your region for better ping.
Click on a server in the list that suits you (PvE, PvP, modded, etc.). Check the server details on the right โ notably the player count, version (should say 41.xx), and any listed Mods (if mods are required, the game will auto-download them on join). If the server is password protected, it will indicate that too.
If the server requires a password, enter it in the "Server Password" field. Choose a username for yourself on that server (this can be anything unique, and it will create a character tied to this name on the server). Choose a password for your account on that server โ this isn't your Steam password, just a password to secure your in-game character on that server.
Hit the "Join Server" button. The game will connect you โ if it's your first time on that server, it may take a moment to download any required mods automatically. Once connected, you'll proceed to the character creation screen to spawn into the world. That's it โ you're in!
If you're trying to join a specific private server or a friend's hosted game that isn't listed publicly, use the Favorites tab in the Join menu.
- Click "Add Server" (or "Add to Favorites") and fill in the details: a name (anything you like), the IP address of the server, and the Port.
- The default port for PZ servers is 16261 unless your host told you otherwise.
- After adding the entry, click on your new entry in Favorites, enter the server password (if any), and your desired username/password for that server, then Join Server.
On Build 41, things are pretty streamlined. Still, if you run into issues at this stage:
- Version Mismatch: Make sure you and the server are on the same version. Compare the version number on the main menu of the game and ensure it matches the server's version.
- Mod Mismatch: If the server uses mods, the game should auto-download them for you when you join. If it fails, you might need to subscribe manually via Steam Workshop.
- Firewall: The first time you host or join a server, Windows may pop up a firewall permission dialog โ make sure to Allow it.
๐งช Opting into Build 42 (Beta Branch Setup)
Build 42 is the ambitious upcoming update, currently available as an unstable beta. It introduces tons of new content (expanded crafting, animals, map expansions, and more), but it's not part of the default game yet. If you want to experience B42, you'll need to switch to it manually.
How to Enable Build 42 (Unstable Beta):
Steam Properties - Beta Selection
- Multiplayer is NOT available initially. The developers have disabled multiplayer in B42's unstable branch on purpose.
- Saves/Mods incompatible: You can't bring your old world or mods straight into B42. Think of it as a clean slate to test new features.
- B42 is a Work in Progress: Expect bugs, imbalance, and frequent patch updates. If you do play it, consider yourself a tester and report any major bugs.
โ "Why Can't I Join?!" โ B42 Multiplayer Status
It's the question on every survivor's mind: When will Build 42 get multiplayer? As of this writing, Build 42 has no official multiplayer support โ and that's by design, not a bug.
No Official MP (Yet) โ Stick with B41 for Multiplayer
The developers (The Indie Stone) disabled MP in the B42 unstable branch intentionally, with the plan to reintroduce it when the build is stable enough. They've done this before: Build 41's testing phase was also single-player for a long time.
What this means for players right now is simple: use Build 41 for all your multiplayer needs. Build 41 is mature, stable, and supports everything from hosting your own server to joining large community servers.
"The game is still on B41โฆ b41 is totally fine and working and the only option for MP."
โ Reddit user
Workarounds for Co-Op on B42
Some clever players discovered that Project Zomboid's built-in split-screen co-op still works in B42, and they leveraged Steam Remote Play Together to share that with friends over the internet.
The Remote Play Together Workaround:
- One player (the "host") launches PZ in Build 42 and starts a single-player game.
- Enable split-screen: The host needs a gamepad (controller). In-game, have the controller connected and press the required buttons to add a new player.
- Create a new character for Player 2. Now you'll have split-screen active (the screen will divide and both characters will be in the game).
- Invite friends via Steam Remote Play: While the game is running, the host opens the Steam Overlay (Shift+Tab) and invites friends to Remote Play.
- Your friend will take control of one of the split-screen slots. Voice chat can be done via Steam or Discord.
- The host's computer bears all the load
- If the host's internet or PC is slow, remote players might see lag
- You're sharing one game state โ can't go too far apart
- Everyone uses the host's mods and settings
๐ Running Both Builds Without Hassle
Some players, especially community server admins or just enthusiastic testers, might want to have Build 41 and Build 42 available concurrently. Here's how to manage that:
Method 1: Switching Back and Forth via Steam
The straightforward (if somewhat slow) method is simply to switch betas in Steam whenever you want to swap.
- Go to Properties -> Betas -> select Unstable for B42
- Let it patch, play it
- When done, go back to Betas and opt-out (back to none) for B41
- Let it patch back down
Method 2: -nosteam Dual Installation Trick
If you're a power user and want both versions available without re-downloading:
- Copy your B41 installation folder somewhere else
- Update to B42 via Steam
- Copy the B42 folder somewhere else
- Create shortcuts for both versions
- Add -nosteam parameter to the B42 shortcut
For most people, the hassle of Method 2 might not be worth it โ simply switching via Steam as needed is simpler. But if you run a server or need to test extensively, the dual installation can be valuable.
๐ง Common Multiplayer Roadblocks & Fixes
Even on stable Build 41, you might hit a few bumps in the road connecting to servers or hosting games. Don't worry โ we've compiled a mini-FAQ of common issues and how to solve them.
This means you (or the server) are on the wrong build. It's a version mismatch error. Double-check that everyone is on Build 41 for now (or if you're intentionally trying a B42 test server, everyone needs to be on B42).
The game will not allow different versions to play together. The solution is simple: coordinate the version. If you accidentally updated to B42 but your friends did not (or vice versa), switch back to the needed version in Steam.
Project Zomboid does a pretty good job of syncing mods: when you join a modded server, it should download the required mods automatically via Steam Workshop. However, sometimes issues occur. Here's what to do:
- Allow the auto-download: When you click join and it says "Downloading Workshop Items," be patient.
- Check what mod is failing: The error will usually list a mod ID or name. Note it.
- Subscribe manually: Go to Steam Workshop, find that mod, and subscribe (or resubscribe to force an update).
This is a generic connection error. If it's a public server, it could simply be down or full. Try again or choose a different server. If it's your friend's hosted game:
On the Join screen (where you enter IP or pick a server), there's a checkbox for "Use Steam Relay". This setting can make a big difference for connections.
If enabled, your client will attempt to connect via Steam's networking if a direct connection fails. This helps if the host didn't port forward or is behind strict NAT.
So, if you can't connect, go back, check (or uncheck) the Use Steam Relay box and try again. The difference can be magical!
Other things to check:
- Ensure the host properly set up port forwarding (port 16261 UDP)
- Use the Steam Server Browser as an alternative
- Check your Firewall/AV settings for Project Zomboid
Unfortunately, Build 41's multiplayer, while fun, isn't perfect. Desync (players seeing things at different positions) especially with vehicles is a known issue. There isn't a client-side fix beyond having a good connection and playing on servers with low ping.
A classic community tip is: if you're convoying, don't drive bumper-to-bumper; give each other space to mitigate the sync issues.
โ Action Steps Recap
๐ Related Guides
Server Administration Guide
Complete guide for hosting and managing Project Zomboid servers with performance tips and security measures.
Build 41 vs 42 Multiplayer
Comprehensive comparison of multiplayer features and stability between Build 41 and Build 42.
Co-op Survival Guide
Master cooperative gameplay strategies and team coordination for surviving together in Project Zomboid.
Server Memory Optimization
Prevent crashes and improve performance by properly allocating memory and managing server resources.
General Error Fixes
Comprehensive troubleshooting guide for various Project Zomboid crashes, errors, and technical issues.
Server Settings Guide
Configure multiplayer settings, sandbox options, and prevent common server issues.
๐ Further Resources
Project Zomboid Official Wiki โ Multiplayer Guide
Detailed info on hosting servers, router setup, admin commands, etc. Great if you plan to run a dedicated server or need advanced config help.
Project Zomboid Forums โ Support Section
The Indie Stone's official forums have a helpful community and devs monitoring issues. If you encounter a weird bug (especially on the unstable build), this is the place to search or ask.
Steam Community Discussions
The Steam hub for PZ is active. You can often find quick answers (like the trick about Remote Play) by searching there. Just beware of outdated posts โ use recent ones for Build 41+ info.
pzfans.com and Reddit (r/projectzomboid)
For the latest community discoveries, mods, and news. Pzfans often posts summary articles (like the one about B42 multiplayer status), and the subreddit is full of tips from fellow survivors.