Players join an SCP: Secret Laboratory server through Direct Connect, by typing your server's IP address and port. Once Northwood has verified your server, it also shows up by name in the in-game server browser, but Direct Connect works from the very first boot.
Get your address from the control panel
Open your server in the control panel. The connection card on the Overview shows the address as IP and port, with a copy button. Send your players the whole thing, for example 203.0.113.10:25600.
The port matters. SCP: Secret Laboratory assumes port 7777 when none is typed, and servers on shared hardware each get their own port, so an address without the port leads nowhere.
Join with Direct Connect
- Start SCP: Secret Laboratory from Steam. The game is free, so nobody needs to buy anything to join you.
- Open the server browser from the main menu.
- Click the Direct Connect button.
- Paste the full address, IP and port, and connect.
Join from the server list (verified servers)
If your server is verified by Northwood, players can also find it in the browser:
- Open the server browser from the main menu.
- Use the search to look for a distinctive part of your server name.
- Select the server and join.
A new server is not in this list until Northwood verifies it. If you want it there, follow how to verify your SCP: Secret Laboratory server.
Players can also mark the server as a favourite and find it under Favourites next time.
Give players a hostname instead of an IP
If you own a domain, an SRV record lets players type something like play.yourdomain.com instead of an IP and port. Create a record named _scpsl._udp.play (protocol UDP) that points at an A record for your server IP, with your server's port as the SRV port. Direct Connect then resolves it for them. A domain cannot be used for verification, which always runs on the IPv4 address.
Private servers and whitelists
If you turned on the whitelist, only players listed in UserIDWhitelist.txt get in, and everyone else is refused at the door. Add each player as their SteamID64 followed by @steam and restart the server. The getting started guide shows where that file lives.
When players cannot connect
Work through this list in order.
"The specified host is not available". The server cannot be reached at that address. Check that it is running (the console prints Waiting for players..) and that the address includes the port.
The server is not in the browser. It is not verified yet. Use Direct Connect, or apply for verification.
Version mismatch after an update. When Steam releases a new version, players update first and your server catches up on its next start. Restart the server from the control panel and try again.
The server is full. Raise max_players in config_gameplay.txt and restart. Stay at 60 or below if the server is verified.
Kicked straight away on a private server. The player is not on the whitelist, or their entry is missing @steam.
For the server side of things, like naming the server and making yourself owner, see the getting started guide. Plans and hardware are on the SCP: Secret Laboratory server hosting page.
