Can't join a game cause screen goes black and white

So after patch 7.9, I was doing fine. All my other friends were having troubles with their clients and in game stuff. While i was perfectly normal. I started playing a few days later and when ever i go in game(like w8ing for people to join the game) My screen will freeze right after the league logo. The screen will go all white and says i have been disconnected. I tried command tabing out of the game but the screen then turns black. So i tried again and again and again untill i restart my computor and tried again but it still would not let me join. After 2o minutes of trying to join i finally did for some reason and i lose the game i was in. And ever since then, my league never worked