Network & Connectivity

Ports & Game Connections

Which ports to check, NAT basics, why a game won't connect.

If your game won’t connect or screams “Strict NAT”, read this.

First, check Known Issues.

What is NAT?

NAT (Network Address Translation) maps your internal IP to the outside world. Some games (especially older P2P titles) care a lot about your NAT type.

NAT TypeCan join othersOthers can join youNotes
OpenBest
Moderate⚠️ Hosting may failCommon
Strict⚠️ Open NAT onlyAlmost always your firewall

Our event network uses enterprise-grade NAT. You cannot change the network NAT. If you see Strict NAT, it is almost always your local firewall blocking traffic.

Which ports to check?

If a game can’t find the server, make sure your firewall allows traffic on these ports.

Service / GamePort(s)Protocol
Web / HTTP80, 443TCP
DNS53UDP
Steam27015–27030UDP + TCP
Counter-Strike 227015UDP + TCP
Call of Duty3074UDP + TCP
Minecraft (Java)25565TCP

How to fix connection issues?

  1. Check your Firewall: Disable Windows Firewall for one minute. If the game works, the firewall was the culprit. Turn it back on and add the game executable to the exceptions list (check both Private and Public!).

  2. UPnP: UPnP is disabled on our network for security reasons. Enabling it on your PC won’t do anything.

  3. VPN: Turn off your VPN. VPNs break local LAN discovery, so you won’t see local servers.

  4. IPv6: Some older games get confused if IPv6 is enabled but there is no IPv6 internet connectivity. Try disabling IPv6 in your adapter settings.

Still stuck?

  1. Check Known Issues first -- if it's listed, we already know.
  2. Post in #support on Discord with this info:
    • Seat number (e.g. Row 4, Seat 12)
    • What's broken, one sentence
    • What you already tried
    • Screenshot or error message
  3. If no reply in 15 minutes, come to the organizer desk.