I've been a Mac user forever. I am about to graduate from graphic design school and needed an upgrade. I purchased a beautiful 27" iMac from eBay. It works wonderfully, looks brand new, and came in the original box. I went with this PARTICULAR computer because it had Parallels, Bootcamp, & Windows 7 & 8 installed. I've never had any of that on my mac, but there are a couple of things I've wanted to be able to do on my old laptop that I couldn't and was excited to get the opportunity. Anyways, it all worked (or worked to the extent of my knowledge) for about 3 days. Then it said I needed to activate windows. I wasn't concerned because I have the original boxes for the parallels and windows 8. But it won't accept either key. I emailed the guy who sold it to me and he sent me another key which also didn't work. Not only do I need help fixing all this stuff and getting it running again, but I also don't completely understand what it all does. Will someone who knows about all of this stuff give me the lowdown and help me to fix it please? Thank y'all so much!