Game error with Patch 9.21

It is letting me log in to League of Legends but as soon as I get there it gives me the message "Patching failed and we're not sure why. Please restart the client to try patching again. (Error code 004)" This started yesterday with patch 9.21.

Initially I was able to log on and get into champ select, but it wouldn't go to the loading screen and put me right to the reconnect option. No matter how many times I hit reconnect it wouldn't open the loading screen, however I will note that it sent me to the after game screen on one occasion after my teammates voted to remake. I downloaded the Hextech repair tool and tried the Force Repatch option, since then it has given me the above message after I log in (I've tried three different accounts and it is the same for all of them). Once I hit okay, it will sometimes show the "loading" option where the play button is, but it will only get to 48% before the message comes back on the screen.

I have more than enough space on my hard rive, I have tried running the game with admin privileges, my internet connection is fine, and I have even tried a reinstall multiple times both with and without a clean uninstall. My computer is only a year old, it is a proper gaming computer and still runs everything else just fine. I have never had this issue before, and it only started yesterday after the patch update.

Any help would be appreciated.