Can't play the game!!!

This started 4 weeks ago when I couldn't open any game mode cause the game would crash every time it went to loading screen, so I decided to reinstall LoL , and I did, and it was running perfectly but after 2 weeks , same thing happened...!!! Now I clean installed windows 7 , installed LoL(currently have no antivirus and firewall is off) and can only open Howling abyss, can;t open Summoner's Rift!!!!! Help pls !!! idk wt to do , it seems like reinstalling it would be useless !!!!!!!!

Thanks in advance !!!