An unknown DirextX problem has occured and League of legends cannot start.

I need help. Everytime i try to join a game a DIrextX problem pops up. Ive tried everything i can find on the internet. I installed the latest version of my driver card. I deactivated then activated it again. I tried restarting my computer. I tried donwloading the latest version of DirectX i have tried absolutly everything. Someone have any tips on how i can fix it? Right now im on Windows 7.