I Need Help

[:1]hey. i use to play d2 a lot back in the day and recently tried getting mine to work again. diablo 2 starter disc's worked fine except for the lod expansion disc. it said upgrade from multiplayer to full even though i picked to do the full dowload. when i put in lod expansion disc. the cd key never popped up and it went through the hole dowload bar and it says put in diablo 2 disc. was wondering if anyone new why it wont show the lod expansion disc key set up so i can type it in. thanks would be greatly appreciated