Product Description:
Blizzard Entertainment took online role playing by storm with their hit title,

World of Warcraft. With mind-boggling improvements in graphics, gameplay networking, and interface

-- really every category

-- this game became the crown prince of the genre.

World of Warcraft players will be excited by the approaching release of the new expansion pack: World of Warcraft: The Burning Crusade.

This pack expands the already massive, award-winning multiplayer online role-playing game by tremendous bounds, adding new races, lands, battlegrounds, professions and items, and much, much more.

Note:
1.) This product is only applicable for the Europe version.
2.) This product contains a CD-Key purchase only and does not include manuals, Installation CDs, and box.

Where do I need to enter my key when upgrading? Is it through the client or on the website in Account Management?
You will need to enter your key either through the installer or on the following web page - https://upgrade.wow-europe.com/expansion/.