[Solved] Can't select other series anymore

Hi,
We have a complete Kartsim-simulator. Yesterday our son pushed "Host" in Rf2


and went trough 1 or 2 screens like this one:


Than pressed exit.

And now we can't select any other Series nor Car.



Could someone help us to figure out what happend?

 

On the steamcommunity someone helped me. so this thread may be deleted.