I just tried logging into the server and when I join I'm getting a message saying "checksum failed, you are being kicked from the server". What does that mean and how do I fix it please?
Read the opening post again and make sure the real name package is installed correctly.
Required extra content
To join the server you will need to copy replace the 'data.acd' files on your PC with those in the real names link below as discussed here and here
Real names update - Install extracted rss_gt_data_real_names_v6 to X:\SteamLibrary\steamapps\common\assettocorsa\content\cars
A checksum is a check that creates a hash of the installed files, in this case the skins and RSS cars and the track and matches that up to what is installed on the server. If it the content isn't the same the hash will be different and it will throw a checksum error.
TLDR: make sure you've installed the correct versions and that the files are working
I'm not sure about the skins.. Either you need to have at least the skin names that the server is using or you'd just see a white car.
The checksum, afaik, only checks the data.acd of the cars (which gets changed by the real name package)
For tracks, it checks the surfaces.ini, which contains stuff like
"kerb 17: type = kerb, grip = 0.95, friction = 1.5, isTrack = 0"
And another file that I can't remember.. A very small one in any case!
So funnily enough you can join a server with a different version of the track if these 2 files are identical and you'll see other cars driving inside the floor and other crazy stuff, since
everything runs locally at the clients, while the server only updates the reported coordinates to all other clients.
Rarely happens though, since one of the files usually changes with each update.
But with non-RD mod-tracks, I've seen some crazy stuff!
This just gives an error during loading, no checksum error.
But for me, the error message is always in the background and the loading screen just gets stuck.
Quite messy...