Game wont start!

Description of the problem " Data/enGB/wow-update-enGB-18273.MPQ: World of Warcraft can't make 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 battle net something..."

That says when i try to open the game...Now, I've tried to run it in "administrator mode" but problem remains.Please help, don't know what to do.

Follow these steps:
1) Restart your PC ( this is important)
2) close your Torrent client and move your WoW folder away from your Torrent's download destination
3) now right click on WoW folder> Properties> remove "read-only".