[CLIENT] Game Won't Update After Initial Install

So I'm trying to download the game for my brother on his computer and the client won't go through the updates.

It reaches about 74% before stopping. It has about 1,400 KBps, but as soon as it hits 74% completion it immediately drops down to 0 KBps and won't update anything anymore (even after leaving it alone for 2 hours to do so).

I've already tried exiting the client and retrying the download, but it does the exact same thing every time I try.

Anyone have any tips for me?