okay so i bought world of warcraft and ive been playing it for a while, but i bought it online, i didnt order the disk. then i did the same with burning crusade and everything worked perfectly, but then i tried to buy lich king, and every time i try to install it after i bought it, (i have a mac by the way) it says: Sorry, the installer was unable to start up.

No installer data could be found. If this problem persists, please contact Blizzard Technical Support.

and when i try to log in it wont let me play for some reason, ive tried so many things to fix it! help!