WoW file won't start

I've downloaded the MoP windows client on my 64-bit windows 10 pc, and whenever i try to open the WoW file this message shows up:

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

follow these steps:
1) Restart your PC ( this is important in your case)
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".