I get an error message when trying to connect to Flight Simulator multiplayer

Although this could be due to a number of different reasons, the most common causes are ports that are not being forwarded on your router or ports that are being blocked by your firewall.

If you are using firewall software on your computer (or the built in Windows firewall), make sure to allow both your simulator (FSX, FSX:SE, P3D, or FS2004) and FSHost Client (if you are using it) through your firewall.

Additionally, you should forward UDP ports 23456, 6073, and 2300-2400 on your router to your computer before trying to connect.

To make sure that your ports are forwarded correctly, you can download and run the FS Port Test tool from our “Downloads” page.