Failed to Connect?

So I get into the game and champ select just fine, but when I try to play an actual game, I get a "Failed to connect" message. It reads "Unable to connect to server. Please check your network connection and attempt to reconnect your game." My wifi connection and such is perfectly fine. League was running fine until yesterday night now all of a sudden this message keeps popping up. What can I do? I really don't want to have to redownload league and stuff.