Second update for 7.1 (1/13/17) is stuck at 0% and disconnects from the servers after a minute

It's always stuck at "Files Scanned: 1 releasemanifest" (or replace 1 with 2) at 0%, and it disconnects from the servers a couple minutes after logging in forcing me to exit. I can't find any folders for League of Legends (other than the one that has the "Highlights" and "Replays" folders in it), so I can't clean out League's folders or anything. Any time I've had this problem with other games, reinstalling the client has never done anything. What do I do? Also, as I was typing this League made the "ping" noise that normally signifies it's done updating, but I went back to it and had the same text as above with the same progress.