i cant play the game help!

so im new to wow i want to play with a friend we want to play WotLK the problem is everytime i try to play the game:

i login then this shows ---> Downloading Update 0% , and then it says patch required press the restart button below to restart wow and download the patch

then is says that the patch failed and if the problem resists to reinstall the game or contact technichal support...

i just downloaded the game

btw im using Wotlk old

you need to log-in by using warmane account name, not email address