How to Install MultiplayerPlus on Schedule 1 (4 to 20 Players)

Schedule 1’s vanilla multiplayer caps you at four players. That cap is hard-coded in the base game — there’s no maxPlayers field in any config you can edit. To run a bigger Hyland Point operation with up to 20 players, you need the community-built MultiplayerPlus mod loaded on both the server and every client.

This guide walks through the full setup: installing MultiplayerPlus on a dedicated server, pinning the version so connecting clients don’t get rejected, and the common errors that catch first-time installers.

What MultiplayerPlus actually does

MultiplayerPlus patches Schedule 1’s hard-coded lobby cap from 4 to a configurable ceiling — the practical maximum is 20 players. Beyond that the game’s netcode starts to misbehave: NPC simulation desyncs between clients, dealer routes break, production lines stall on remote clients, and the server CPU spikes hard.

The mod is a community project by MedicalMess, mirrored on Thunderstore and Nexus Mods. It runs through MelonLoader (the universal Unity mod loader) — so you need MelonLoader installed first.

Prerequisites

• A Schedule 1 dedicated server (we recommend XGamingServer’s Schedule 1 server hosting — MelonLoader and the DedicatedServerMod are pre-installed).
• MelonLoader installed at a version compatible with your Schedule 1 build (check the DedicatedServerMod release notes for what’s tested).
• The latest MultiplayerPlus.dll from Thunderstore or Nexus.
• Every player who wants to join needs MultiplayerPlus locally too — both-sides mod.

Install MultiplayerPlus on the server

1. Download MultiplayerPlus from Thunderstore (search “MultiplayerPlus”) or Nexus Mods. You want the latest .dll.
2. Stop your server from the panel Dashboard.
3. Open File Manager in your XGamingServer panel and navigate to the Mods/ folder (sits next to Schedule I.exe).
4. Upload MultiplayerPlus.dll — drag and drop, or click Upload.
5. Start the server. Watch the Console output — MultiplayerPlus should log that it loaded successfully and the new cap is active.

There’s no maxPlayers field to edit in server_config.toml — the mod raises the cap internally. If you want to verify, run serverinfo from the Console tab to see the current player limit.

Install MultiplayerPlus on each client

Every player who wants to join needs the same MultiplayerPlus .dll on their copy of the game. Send your players these steps:

1. Install MelonLoader on their Schedule I install (Steam → right-click Schedule I → Manage → Browse local files → run the MelonLoader installer at the same version the server uses).
2. Drop MultiplayerPlus.dll into the local Mods/ folder.
3. Also drop the DedicatedServerMod client launcher .dll there — that’s what lets them connect by direct IP instead of Steam friends.
4. Launch Schedule I via Steam.
5. From the join screen the DedicatedServerMod client launcher adds, enter the server’s IP and port.

Pin the version so mismatched clients can’t connect

If you’re running a serious group, version drift is the most common pain point — a player updates MultiplayerPlus mid-session and suddenly can’t connect. The DedicatedServerMod’s client mod policy fixes this:

Edit client_mod_policy.toml via the panel File Manager:

[strictPinnedCompanionHashes.bars.multiplayerplus]
modId = 'bars.multiplayerplus'
pinnedSha256 = [
  '<paste the SHA-256 of the exact MultiplayerPlus.dll you handed out>'
]

Get the hash with PowerShell:

Get-FileHash -Algorithm SHA256 path\to\MultiplayerPlus.dll

Or on Linux/macOS:

sha256sum path/to/MultiplayerPlus.dll

Now any client running a different MultiplayerPlus build gets rejected at connect with a clear policy-violation reason.

RAM and CPU sizing for 20 players

Empty Schedule 1 servers already use about 2.6 GB RAM and 200% CPU at idle (two saturated cores) because MelonLoader’s headless Unity loop isn’t aggressively throttled. Adding 20 modded players on top isn’t free.

Target players	Recommended tier
4 vanilla (no MultiplayerPlus)	Rookie 8 GB / 3 cores
Up to 10 modded	Pro 12 GB / 4 cores
Full 20-player MultiplayerPlus cap + content mods	ProMax 16 GB / 6 cores
Heavy mod stacks / multi-server	Ultimate 24 GB / 8 cores

If you’re upgrading a hosting plan mid-campaign on XGamingServer, your save data and mod stack carry over — no reinstall needed.

Common errors

“Mod hash mismatch: MultiplayerPlus.dll” — Client is on a different MultiplayerPlus version than the server. Send them the exact .dll you have in the server Mods/ folder.

“Required mod missing: MultiplayerPlus” — Player hasn’t installed the mod yet, or installed it into the wrong folder. Re-run MelonLoader installer and verify the Mods/ folder is next to Schedule I.exe.

“MelonLoader version mismatch” — Their MelonLoader is a different version than yours. Pin to the version the DedicatedServerMod release notes call for and share that exact installer.

Server starts but cap is still 4 — MelonLoader didn’t load MultiplayerPlus. Check the Console output for red [ERR] lines naming the failed mod, and confirm the .dll is in Mods/ (not UserData/ or some other folder).

Why dedicated hosting matters at 20 players

Steam P2P co-op uses the host’s machine as the authoritative server. With 4 players that’s manageable; with 20 players running MultiplayerPlus, the host’s PC becomes a bottleneck — upload bandwidth, CPU contention with the host playing the game, and the world disappearing the moment they log off.

A real dedicated server keeps the world running 24/7 regardless of who’s online. It also handles the resource floor (2.6 GB / 200% CPU at idle) on hardware sized for it rather than on someone’s gaming rig.

If you don’t already have a server, rent a Schedule 1 dedicated server with MelonLoader and the DedicatedServerMod pre-installed — you skip the entire setup chain above and your crew can join via IP within minutes.

Related guides

• MultiplayerPlus reference docs
• Client mod verification — pin hashes for your mod stack
• DedicatedServerMod setup walkthrough
• Schedule 1 server config generator — builds the three TOML files automatically