PZ Server Hopping: Surviving Build 41 & 42โ€™s Experimental Zones

PZ Server Hopping: Surviving Build 41 & 42โ€™s Experimental Zones

Survive together or die trying โ€“ here's how to jump into Project Zomboid multiplayer on both the rock-solid Build 41 and the bleeding-edge Build 42.

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.

Skip to the Quick-Start โ†’
๐Ÿš€ Quick-Start Guide ๐Ÿงช Build 42 Beta โ“ MP Status ๐Ÿ”„ Running Both Builds ๐Ÿ› ๏ธ Troubleshooting

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:

  1. Update to Build 41: 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.
  2. Open the Join Menu: From the main menu, click on "Join". This opens the Server Browser interface where you can find servers or connect directly.
  3. Find a Server (Internet tab): 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 to narrow it down.
  4. Select a Server: Click on a server that suits you. Check the server details โ€“ notably the player count, version (should say 41.xx), and any listed Mods.
  5. Enter Password and Username: If the server requires a password, enter it. Choose a username and password for your account on that server.
  6. Join the Server: Hit the "Join Server" button. The game will connect you โ€“ it may download required mods automatically.

Note: When joining a server from the Internet list, you'll set a unique username and password for your character on that server.

Direct Connect (Favorites tab)

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:

  1. Click "Add Server" (or "Add to Favorites")
  2. Fill in the details: a name, the IP address of the server, and the Port (default: 16261)
  3. Click on your new entry in Favorites, enter credentials, and Join Server

Invite via Steam Friends

If your friend is hosting via the in-game "Host" option:

  1. Launch Project Zomboid (Build 41)
  2. Have them invite you through Steam's friends list
  3. Accept the invite and the game will connect you automatically

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, 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):

  1. Open Steam Properties: Completely close Project Zomboid if it's running. In your Steam Library, right-click Project Zomboid and select "Properties."
  2. Go to Betas Tab: In the Properties window, click the "Betas" tab. You'll see a dropdown menu for beta branches.
  3. Select "Unstable" Branch: Click the dropdown and choose "Unstable" (this is the Build 42 branch). Steam should immediately start downloading the update.
  4. Wait for Download & Launch: Let Steam finish downloading B42. Once done, launch Project Zomboid and verify the version at the bottom.
  5. Backup Your Saves (Recommended): If you care about any single-player saves from B41, back them up before playing on B42.
Steam Properties > Betas Tab > Select "Unstable"
SELECT THE BETA YOU WOULD LIKE TO OPT INTO:
Note: This will download the unstable version of Project Zomboid

What's New in Build 42 (and what's not):

Build 42 brings a laundry list of new features and improvements:

  • Expanded map with new areas (and underground sections)
  • Farm animals and wildlife
  • Revamped crafting system (blacksmithing, pottery, etc.)
  • Improved lighting and optimized performance
  • Enhanced skill progression system (check our VHS skill guide for B41 vs B42 differences)
  • And much more!

IMPORTANT: Multiplayer is NOT available initially in Build 42. The developers have disabled multiplayer in B42's unstable branch on purpose. You won't see a "Join" button at all in the B42 menu.

Other limitations:

  • Saves/Mods from B41 are incompatible with B42
  • B42 is a Work in Progress - expect bugs and frequent updates

"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. What this means for players right now is simple: use Build 41 for all your multiplayer needs.

If you've already opted into B42 but now want to play multiplayer, you'll need to switch back to B41. Simply go back to Steam Properties -> Betas and select "None" (or the "NONE - Opt out of all betas" option). This will downgrade your game back to the latest stable Build 41 release.

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.

B42 Split-Screen + Remote Play Workaround:

  1. One player (the "host") launches PZ in Build 42 and starts a single-player game
  2. Enable split-screen: The host needs a gamepad (controller) to add a new player
  3. Create a character for Player 2 - the screen will split
  4. Invite friends via Steam Remote Play: Open Steam Overlay (Shift+Tab) and invite friends
  5. Assign controllers to friends when they join

Note: This method works but has limitations: the host's PC bears all the load, players can't go too far apart, and everyone uses the host's mods and settings.

Warning: Some community attempts to "hack" multiplayer back into B42 by editing game files have been unsuccessful. These methods might cause crashes or other issues. The safest approach is to wait for official MP support.

Running Both Builds Without Hassle

Some players might want to have Build 41 and Build 42 available concurrently. Maybe you play on a B41 server regularly, but also want to experiment in B42. Here's how to manage that:

Option 1: Switching via Steam

The straightforward method is to switch betas in Steam whenever you want to swap:

  1. Go to Properties -> Betas -> select Unstable for B42
  2. Let it patch to B42, play it
  3. When done, go back to Betas and opt-out (back to "none") for B41

Pro: Simple and officially supported
Con: Need to download differences each switch

Option 2: -nosteam Dual Installation

For power users who want both versions available without re-downloading:

  1. Copy your B41 install folder to a backup location
  2. Update to B42 via Steam
  3. Create shortcuts to both versions, adding "-nosteam" to the B42 shortcut

Pro: Both versions ready anytime
Con: Manual updates needed for copied version

Note for the future: When Build 42 eventually becomes the new stable, the roles flip. B42 will be "none (default)" and B41 will likely be available as a legacy branch (perhaps called legacy_41_78 or similar).

Common Multiplayer Roadblocks & Fixes

Q: "Client version (41.78) does not match server version (42.0) โ€“ what gives?"

This means you (or the server) are on the wrong build. It's a version mismatch error. Double-check that everyone is on the same build:

  • For multiplayer, all players should be on Build 41
  • The game requires an exact version match
  • In the server browser list, servers show their version number

Q: "Workshop item version different than server's" or "Mod Rejections"

Project Zomboid syncs mods automatically, but sometimes there are issues:

  1. Allow auto-download: When joining, let "Downloading Workshop Items" finish
  2. Check what mod is failing: Note the mod ID from the error
  3. Subscribe manually: Go to Steam Workshop, find that mod, and subscribe
  4. If already subscribed, unsubscribe and resubscribe to force an update

Q: "Connection failed" or "Server not responding"

For connection issues:

  • Check port forwarding: The host needs port 16261 UDP open and forwarded (see our complete port forwarding guide)
  • Try "Use Steam Relay": On the Join screen, toggle this checkbox
  • Check your Firewall/AV: Make sure Project Zomboid is allowed through
  • Use Steam Server Browser: Add the server via Steam itself (View -> Servers -> Favorites)

Pro Tip: The "Use Steam Relay" toggle can make a huge difference for connections. If you can't connect, try toggling this option and attempt again.

Q: "Desync" and lag in B41 โ€“ cars teleporting, zombies hitting me from far away

Unfortunately, Build 41's multiplayer isn't perfect. Desync issues, especially with vehicles, are known:

  • Play on servers with low ping
  • When driving together, don't drive bumper-to-bumper; give each other space
  • Check if the server has any anti-lag mods

This is one reason the devs are taking their time with B42 MP โ€“ they want to address these problems.

Action Steps Recap (No Player Left Behind!)

  1. Choose Your Build Wisely: Use Build 41 for any and all multiplayer fun. Only use Build 42 if you're testing new features solo.
  2. Switching Builds: In Steam, go to Properties โ†’ Betas. Select "None (opt-out)" for Build 41 stable, or "Unstable" for Build 42 beta.
  3. Joining a Server (B41): Click Join -> find a server on Internet tab -> enter credentials -> Join Server.
  4. Build 42 Workaround: If you must play B42 with friends now, host a split-screen game and use Steam Remote Play Together.
  5. Troubleshooting: Always check game versions, enable "Use Steam Relay" for connection issues, keep mods updated. For hosting issues, see our port forwarding guide.
  6. Server Administration: If you're planning to host your own server, check out our server admin guide for setup and management tips.
  7. Future Updates: Keep an eye on official news for when Build 42 gets a multiplayer patch.
  8. Have Fun & Communicate: Coordinate with your friends to ensure everyone is on the same build and has the same mods.

Further Resources

Project Zomboid Official Wiki

Detailed info on hosting servers, router setup, admin commands, etc. Great if you plan to run a dedicated server.

Project Zomboid Forums

The Indie Stone's official forums have a helpful community and devs monitoring issues.

Steam Community

The Steam hub for PZ is active with quick answers about game updates and features.

Patch History

Personal Anecdote

Back when Build 41's multiplayer finally dropped in late 2021, I remember desperately trying to get my old college buddies to join me in West Point. We spent an entire evening troubleshooting why one friend couldn't connect โ€“ only to realize he was on the wrong beta branch. It reminded me of LAN parties in the early 2000s, checking game versions and patch numbers before a game of Counter-Strike. Project Zomboid gave us that old-school tinkering feel, but once we got it working, oh boy, it was worth it. The moral of the story: the struggle to connect makes the success that much sweeter.