: If UPnP doesn't work, you'll need to log into your router (often at 192.168.1.1 or 192.168.0.1 ). Navigate to the Port Forwarding section and create a new rule: Protocol : UDP Port Range : 16000 (both Start and End)

Even with the port open, Windows 11 may block the GameRanger client executable ( GameRanger.exe ) itself. You need to ensure the app is whitelisted.

If it isn't listed, click , browse to the GameRanger installation folder, and select GameRanger.exe . The Real Culprit: Port 16000

After every change, (right-click system tray icon → Exit, then relaunch). The firewall test runs only at startup.