A possible solution for connection issues

I couldn’t seem to find this solution on the internet, so I figured it out myself after quite some infuriating time. So, I’m writing this to hopefully let others know of a potential fix for when you are unable to have a stable connection, or just not connect to another’s server at all.

In my situation, I’ve experienced long loading times (endless), crashes, Socket Error Codes and getting disconnected a short while (a minute or so) after joining one of my friends’ servers. We all have the VPN Hamachi to stay on a network together. I could join one of my friends and stay on there with no issues, but not the other 2, when they hosted a server. If I tried to host, they would get disconnected after joining after driving around for a minute.
I thought mods were the issue at first, since I got stuck on specific mods on the rare occasion I was
actually loading in.

I tried reinstalling BeamNG, BeamMP, Hamachi, verifying files, having no mods, restarting my PC, having UPnP on and a whole lot more.

And then it struck me… The fix was going to my own network’s settings (Default Gateway - login etc.) [cmd → ipconfig → copying Default Gateway and pasting into a browser URL] On my network’s settings I could change the NAT type from “Symmetric” to “Post restricted cone”. I believe that in short these two just mean “Restricted” and “Open”, as I know from other troubleshooting stuff I’ve done. Switched to “Post retricted cone” and the problems were gone. I could connect with no problems, no slow loading time.

interesting. glad that helped you. unfortunately, this method isnt really that great, since literally everything around us usually uses symmetric NAT and for a good reason. if you do get “failed to close socket” error or warning, then you need to check if the port that the server is using is actually available on YOUR end. due to the way tcp/ip works, connections can not be closed immediately.

you can see a list of ports and sockets in cmd via “netstat -aon”, though wireshark would be better visually. the default launcher port that SHOULD be “listening” (i.e. open, as in available) is 4444, you can change it in the multiplayer options at the very bottom. you could try changing this if you get constant disconnects, timeouts, etc.

i hope i am leading you in the right direction. so to anyone having this issue - if you have a lot of apps that require the internet running in the background, especially stuff that has to do with torrent, p2p, stuff like that can and will occupy a port that is needed for beammp. i hope you will finally figure it all out and never ever get these random “you have been disconnected from the server” popups again.

take care <3