I have no clue on how this happens, as far as I can see it happens with all tracks. I get this error message when I leave an on and offline race, but only when I drove a few laps.

It started happening after upgrading to patch U. I don't think I had it before, at least not with the patch we had a long time, with all those patches after each other I can't really remember if it started with one of the patches, or it only started now.

It might be something stupid, but it's annoying cause it makes that error sound every time I leave a server. And I don't want to delete the error sound

Just goto your LFS/data/knw folder and delete that file. That file is just the 'racing groove' path (that dark line on the track)... and it must've become corrupted somehow.

Just delete it, and go drive on the track again, and it should make a new one.

I don't feel like racing now, so I'll delete all the files now, and try tomorrow.
Thanks for the help, I knew it was something stupid, but smart people don't notice stupid stuff