MoP doesnt work

Hello everyone, I've just downloaded MoP 5.4.8 and it doesnt work when I try to run it. Only this statement appears:
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

Any tips? :)

Go to the folder you have WoW installed, go on properties and uncheck read-only. It should work.

Here; http://tinypic.com/view.php?pic=2qm3fns&s=9