So when I join a server , I can see other players but they can't see me. When I try to bang into a car in the server , my car just bounces off and doesn't affect the other driver. Any help ?
So very likely your TCP connection to server works ok, which allows you to see the server + connect, and if you see other players driving around, you are also receiving UDP packets as well, but your UDP packets are going nowhere, so server has no updates of your driving.
Wasn't there some option in LFS to switch to slow TCP for MP? Try to search options menu or forum.
And if this is the problem, you should have problems with most of the MP games, not only LFS.
Yes there is that option.. Press N for connection list in right bottom corner. Then press UDP behind hostname on top of the list. It will switch to TCP (in red).
If you can, use a cable to connect to your modem. Wi-fi is horrible for gaming.
Also, make sure you don't have anything else running in the background on your computer that might be trying to use the internet at the same time. Programs like Skype, for instance, can be bad upstream bandwidth-hogs.
Sadly I don't think there is a possible solution for now, we need for scawen to look into it, because I never had such problem before the multiplayer update.
I suspected the ISP for blocking LFS somehow, but since all other multiplayer games are working perfectly so it's probably from how LFS handle UDP/TCP interface.
But it working using VPN software, so that's why I suspected the ISP.
From the next test patch, if you select TCP for position packets, then your LFS will also send position packets to the host using TCP. So it will be TCP in both directions.
NOTE: if you want to test this in the next test patch (K8) this new feature will only work if you join a K8 server. If you join a K7 or older server, your LFS will still send UDP position packets.