With CGNAT, you share a public IP address with hundreds of other users. You cannot forward ports because you don't own the public IP – your ISP does.
For sim racers, few things are more frustrating than setting up a perfect online lobby or joining a ranked race, only to be met with that dreaded red text: With CGNAT, you share a public IP address
This guide provides a deep dive into every possible cause and solution, from basic port forwarding to advanced router settings and third-party software conflicts. By the end of this article, you’ll be back on the track, side-by-side with other drivers. Before we start fixing, let’s understand the problem. Assetto Corsa (and its modded cousin, Assetto Corsa Competizione) uses a peer-to-peer (P2P) networking model mixed with a central server list (the "Master Server"). By the end of this article, you’ll be
This error effectively locks you out of multiplayer. It can appear when trying to join a friend’s lobby, a dedicated server, or even when attempting to browse the server list via Content Manager or the vanilla launcher. This error effectively locks you out of multiplayer
Do not let this error ruin your sim racing weekend. Work through this guide methodically, and you will find the solution. See you on the track – and may your ping be low. Share it with a friend who keeps getting disconnected from the lobby. For more Assetto Corsa troubleshooting, check our guides on "CSP settings for online racing" and "Best VPNs for sim racing without CGNAT."