An unknown DirectX error has occurred and LOL cannot start problem

What is up y'all. I'm having a problem that Leaugue doesn't work because of that an unknwon directx error has occurred and LOL cannot start, Please make sure your video card is using the latest video drivers from the manufacturer I tried everything for that. I refered to youtube video to fix it, but all failed. Please if you guys know how to fix this issue, let me know to fix it. My laptop is alienware, perfect graphic everything is totally fine. what is wrong with my laptop and league? Help me!! Thank you