I'm trying to play my Diablo 3 single player campaign but am unable to resume my game, as the button is is grayed out and says "Only Available to Party Leader". I have never played online with people before, only with myslef. I am trying to play my game on a windows when I was originally on a mac, so I'm not sure if that has anyting to do with it, but they are both using the same account. I also tried going back to see if I could play it on my mac, but the resume game button is greyyed out on that one as well. Any help would be appreciated.