having problem starting the game.

i just downloaded the MoP version. and i got a launcher that only said wow and when i hold my mouse over it it said world of warcraft retail. and i don't have the wow.exe one. i have no clue what to do. when i press the wow launcher it says """"""""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 this 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"