I have two iMacs. One is newer and came with Yosemite... Or was upgraded out of the box. The other is older... And is running Mavericks. I remember when I upgraded the older one to where it is now, I had to not turn on some feature...maybe iPhoto cloud library or something? Or Photos until I had done something else. It has been too long and now I can't remember what it was. I have the old computer off for months but need to get it ready for my kids to use. I don't want to ruin my photo library etc on my new computer. From my ridiculous description can anyone figure out what I am trying to do?? I think it was also a setting choice in the iOS 8 update. Thanks!!