Ok so this is how it happened. I used all 20 AI cars and and i did not join the race and i saved replay and it screwed up the single player system. I can't join single player race now but only AI cars can drive now. What do i do?

I used up all AI spaces, then saved replay, ended race and now i can't join even with no AI.

Type /clear to get rid of the AI, or simply click on the '-' (minus) key to the left of the AI's name to remove one at a time.

It really does sound like you've added 20 AI's and not left room for yourself. Remember, only 20 on track in single player.

make a screenshot from the sp enter screen

This is what it looks like

strange. -.-

Bump for someone to help

Download a fresh LFS, upgrade it to the latest patch, and you'll not get the same problem. I hope so.

I don't know how it happened, but you could open your data\grids folder and delete the cfg.rac file (you can safely delete any of those save grid files).

Yes it works! I love you Scawen for making LFS and helping me

EDIT: I am not gay

damn! beat me to it, that happened to me too once, too me forever that I could delete grids