When you receive an error such as: "read tcp 85.17.189.120:11757->255.255.255.255:51988: wsarecv: An existing connection was forcibly closed by the remote host."
This error indicates that the connection was closed by the server.
The cause of this error is when you're using more cars than the amount of pit boxes on the track. (e.g. 24 cars, but a track with 16 pit boxes)
To resolve this you can either reduce the amount of cars offered, to match the pit boxes for the track.
Alternatively you can use a different track which has enough pit boxes for all the cars.