MoP download not working

I've downloaded MoP and it sates this:
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

I also checked and saw no Realmlist.wtf, is this a problem due to Wotlk being in the same main folder/ is there a fix, i even redownloaded it to see the same problem. And also have ran it as Admin and still same thing.

I've managed to get it working by modifying properties. But still dont see a Realmlist.wtf to switch servers to a PVP server i play on.