I would greatly appreciate some assistance plzFollow

Ok so let me explain the pickle I am in. my older brother had a wow account but no longer plays, and until recently i nvr had an interest in playing. i wanted to try it out so he gave me his wow disc and his disc for BC. I asked him if it would install ok due to him already having used the disc on his pc. he said it should be fine, the original wow installed fine it seems but BC installs to 74% or so then gives me an error saying "the file "c:/users/public/games/world of warcraft/data/common-2.MPQ" could not be found (open archive :: Execute)" I went to trouble shooting on battle net and it said something like " the common-2 MPQ error message means the world of warcraft install is already up to date, and to remove the disc and launch the game" but my brother was just gonna give me his account id and password when it finished (which he hasn't done yet), so i have no way of testing the whole trouble shooting thing. my question is if any has any helpful suggestions or has experieced this?

cuz hes been out since i started the install really. i'll probly have to wait till he gets up ...10:00 - 12:00. also i was asleep till 9:00pm cuz i was up for like 30 hrs strait due to problems with my pos car

iirc, that particular error was due to a mass manufacturing defect, or to that effect was the explanation I heard at the time.

Aside from the obvious frustration/worry I had at the time dealing with it (in my case getting lucky enough to get a burnt copy from a coworker that worked only once to finish the original/first install), it shouldnt be such a huge worry now as once you have the game discs (their code keys specifically) registered to the battle.net account, digitally downloading from then on, for whatever reason, is almost worry free.