Pandaria Can't run the game.

[TokyFallout]

Hey ya'll.

I've downloaded the full MoP client from the website here and whenever I try to run it using the WoW.exe file I get about a minute of nothing, followed by the error message: "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 Word of Warcraft folder or try running the game in administrator mode. For more information, see: https:/battle.net/support/article/6910".

I have the LK client, without the WoD models and it's running perfectly for years now, also I do have retail installed.

Thank you all in advance.

[Zelta]

[TokyFallout]

Thank you!