Satisfactory Server Can't Connect? Fix Server Manager Errors

When you can't connect to a Satisfactory server, the cause is usually one of three things: port 7777 is only open for UDP when it needs UDP and TCP, port 8888 TCP is closed, or the game and server are on different versions. Since update 1.1, the server needs both ports, and many older guides only mention the first. This guide covers the error messages people see and how to fix each one.

Quick fix

1. Add the server through Server Manager, not a join code or the old Join Game menu.
2. Forward 7777 UDP and TCP and 8888 TCP to the server, and allow them through the firewall.
3. Keep the external and internal port numbers the same.
4. Update the server and every player to the same version and branch (Stable or Experimental).
5. Check the clock and time zone on your PC and the server are correct.
6. If you self host with -multihome=0.0.0.0, remove it.

Which error are you seeing?

Open the right ports

Satisfactory 1.1 uses two ports:

The old ports 15000 and 15777 from early access are no longer used by current versions, so forwarding them alone will not help.

Common mistakes:

• 7777 forwarded for UDP only. Server Manager uses TCP on 7777 to talk to the server API. You need a rule for both.
• 8888 missing. The server shows as online, you click Join, and it hangs on the loading screen. That is almost always 8888 TCP.
• Different external and internal port. Remapping 7777 to another number on the router is not supported. If you run the server on 7778, forward 7778 to 7778.
• Firewall. On Windows, allow the ports in Windows Defender Firewall. From an admin Command Prompt:

netsh advfirewall firewall add rule name="Satisfactory UDP" dir=in action=allow protocol=UDP localport=7777
netsh advfirewall firewall add rule name="Satisfactory TCP" dir=in action=allow protocol=TCP localport=7777,8888

On Linux with ufw:

sudo ufw allow 7777
sudo ufw allow 8888/tcp

Our port forwarding guide walks through the router side. If your router's WAN IP does not match your public IP, your internet provider uses CGNAT and forwarding will not work until you get a public IP.

Add the server correctly in Server Manager

1. Open Server Manager from the main menu and click Add Server.
2. Put only the IP in the address box, for example 203.0.113.10, and 7777 in the port box. Pasting 203.0.113.10:7777 into the address box can fail.
3. If you are on the same network as the server, use its local IP such as 192.168.1.50. Friends outside use the public IP.
4. For an IPv6 address, put it in square brackets, like [2001:db8::10].

Joining any other way skips the encryption handshake and gives the "Encryption token missing" error.

Match versions and branches

The server and every player must be on the same patch and the same branch. If one player opted into Experimental on Steam or Epic, they cannot join a Stable server. After every update, self hosters rerun SteamCMD:

steamcmd +force_install_dir "C:\satisfactory-server" +login anonymous +app_update 1690800 validate +quit

For the Experimental branch, add -beta experimental after the app ID, and make sure everyone playing is on Experimental too.

Fix "Certificate is not yet valid"

The server uses a security certificate, and your PC checks it against its own clock. If the date, time or time zone on your PC or the server is wrong, the certificate looks like it is from the future. Turn on automatic time and time zone in Windows settings, sync the clock, and try again. Fix the server's clock too if you run it yourself.

Self hosting quirks

• Remove -multihome=0.0.0.0. Older guides recommended it. Since 1.0 the server listens on IPv4 and IPv6 by default, and this option now causes connection failures on some systems.
• Docker. If the server runs in Docker and nobody can connect, try host networking instead of bridge mode, or make sure both ports are published for the right protocols.
• Server stopped responding after a player left. A known bug can leave a server unreachable. Restart the server.
• Running out of memory. A big factory can make the server freeze or crash while loading, which looks like a timeout. See how much RAM a game server needs.

Can't connect to a GamezServers server

On a hosted server, ports 7777 and 8888 are already open and there is no router or firewall on your side to fix. If you still cannot connect:

1. Check the server is Online on your dashboard.
2. Copy the IP from the top of the control panel and add it in Server Manager with port 7777, IP and port in separate boxes.
3. Restart the server after a Satisfactory patch so it runs the new version, and make sure you are not on the Experimental branch.
4. Check your PC's clock if you see a certificate error.
5. Open the Console tab to see whether the server has finished loading your save.

FAQ

What ports does a Satisfactory server need?

7777 over UDP and TCP, plus 8888 over TCP. Keep the external and internal numbers the same.

Why is my Satisfactory server stuck on the loading screen?

Port 8888 TCP is closed. Forward it and allow it through the firewall.

What does "Failed to connect to the Server API" mean?

Server Manager cannot reach the server over TCP 7777. Forward TCP as well as UDP, check the address, and remove -multihome if you use it.

Can Epic and Steam players join the same server?

Yes, as long as they are on the same version and branch.

Skip the ports

Two ports, two protocols and a firewall make home hosting fiddly. A hosted server comes with its own address and everything already open. See Satisfactory server hosting or the quick start guide.