My Client does not allow me to open links

Everytime i try to open a n link there is just an error report i also tried to reinstall the game and i tried tie hextech repair tool about 4 times where i already sayed it shall reinstall the client or just the patches and i dont know what to do anymor if somebody could tell my what to do so it works again it would be very nice and maybe in GERMAN because i can understand it better TY