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StarRupture Co-op & Multiplayer Fixes (PC/Steam)

Having trouble connecting to friends or experiencing desync? This guide covers connection troubleshooting, port forwarding, and known multiplayer issues in StarRupture's Early Access.

🎮 Co-op Basics

StarRupture supports up to 4-player co-op multiplayer, with one player hosting the session.

Feature Details
Max Players 4 (including host)
Hosting Method Player-hosted (no dedicated servers from developer)
Network Service Epic Online Services (EOS)
Cross-Play Not confirmed
Early Access Note: Multiplayer is still being refined. Expect occasional bugs, disconnects, and desync issues. Report issues to help the developers improve.

🔌 Connection Troubleshooting

Start with these checks if you can't connect to friends.

Quick Checklist

  1. Same game version: All players must be on the same version (check in Steam)
  2. Stable internet: Test your connection; avoid WiFi if possible for hosting
  3. Restart everything: Close game, restart Steam, restart router
  4. Verify game files: Steam → Right-click StarRupture → Properties → Installed Files → Verify integrity
  5. Check Steam status: Ensure Steam's online services aren't down

Firewall & Antivirus

  1. Open Windows Defender Firewall
  2. Click "Allow an app through firewall"
  3. Find StarRupture (or add it manually via "Allow another app")
  4. Ensure both Private and Public are checked
  5. If using third-party antivirus, add StarRupture to its exceptions/whitelist

🌐 Port Forwarding

If you're hosting and friends can't join, you may need to forward ports on your router.

Port Protocol Purpose
7777 TCP + UDP Main game traffic
30010 TCP Server management (dedicated servers)

How to Port Forward

  1. Find your router's IP address (usually 192.168.1.1 or 192.168.0.1)
  2. Access router admin panel in a web browser
  3. Find "Port Forwarding" or "NAT" settings (location varies by router)
  4. Create a new rule:
    • External/Internal Port: 7777
    • Protocol: TCP and UDP (or "Both")
    • Internal IP: Your PC's local IP address
  5. Save and restart router
Find your local IP: Open Command Prompt, type ipconfig, find "IPv4 Address" under your network adapter.

🏠 LAN Connection Issues

StarRupture uses Epic Online Services (EOS), which can complicate LAN play.

Common LAN Problem

If you're hosting a server on your local network, you (the host) may not be able to connect using the LAN IP address, even though external players can connect via your public IP.

Workarounds

  1. Use your public IP: Even on LAN, try connecting via your public IP (find it at whatismyip.com)
  2. Check router for Hairpin NAT: Some routers support "Loopback NAT" or "Hairpin NAT" which allows this; check router settings or documentation
  3. Test via mobile data: As a test, have one player tether to phone data to confirm the public IP connection works
Note: Due to EOS, true "offline LAN" play may not be possible. An internet connection is typically required.

⚠️ Desync Issues

Desync occurs when players see different game states. This is a known Early Access issue.

Common Desync Symptoms

  • Recently placed structures don't appear for other players
  • Players can walk through objects that exist for the host
  • Map markers or progress not syncing between players
  • Enemies dying with a delay for non-hosts
  • Items appearing different for each player

Mitigation Steps

  1. Save and reload: Have the host save the game, all players disconnect, then rejoin
  2. Avoid rapid building: Building too quickly can cause sync issues; pause between placements
  3. Reduce player count: Fewer players = less desync risk
  4. Host with best connection: The player with the most stable internet should host
  5. Update the game: Ensure all players are on the latest patch
Known Issue: Significant desync may require starting a new session. This is an Early Access limitation that developers are actively working on.

📉 Multiplayer Performance Issues

  1. Lower graphics settings: Hosting is CPU-intensive; reduce settings to reduce host lag
  2. Limit base complexity: Very large/complex bases can cause performance issues for all players
  3. Close background apps: Free up bandwidth and CPU for hosting
  4. Wired connection: Use Ethernet instead of WiFi for hosting

❓ FAQ

Can I play with friends on different platforms?

StarRupture is currently PC-only (Steam). Cross-play with other platforms is not available.

Why do I keep disconnecting?

Check your internet stability. If the host's connection is unstable, all players will experience disconnects. The host should use a wired connection if possible.

Can I run a dedicated server?

Community-run dedicated servers may be possible, but official dedicated server tools are not widely available yet. Check Steam forums for community solutions.

My friend can join but I can't join theirs. Why?

This is usually a port forwarding or NAT issue on your end. The person who can be joined likely has more permissive network settings or has forwarded ports.

Is there local split-screen co-op?

No, StarRupture does not support split-screen. Each player needs their own PC and copy of the game.

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