Unable to run the game.

I downloaded the full MoP torrent, and I've double clicked on wow-32 (kind of odd they'd go for 32 bit, I have a 64-bit machine but shouldn't affect it too much).

The process World of Warcaft Retail (32 bits) appears in my task manager, with a constant ram usage of about 4.5mb, but the game never actually starts up.

It eventually ends, with this message.

Data/enGB/wow-update-enGB-18273.MPQ: World of Warcraft can’t make a required change to an archive file. Be sure you have write permission for the World of Warcraft folder or try running the game in administrator mode. For more information, see: https://battle.net/support/article/6910

Yes, I'm running it as administrator and yes I have permission.

Mods, feel free to delete this topic. I am apparently blind and didn't notice the FAQ had this exact error.