I can't update League, it just doesn't work

So, bit of an issue, but I can't patch my league of legends. I start it up like normal, and it prompts me to restart the client to update, everything's normal so far.

The pop-up appears for patching like normal, but then it says "patching failed and we're not sure why. Please restart the client to try patching again. (error code 004)"

I've tried restarting the client, and I've tried multiple times over the course of yesterday and now today with no success. Anyone else experiencing this?