At my workplace the previous sysadmin had installed a pirated version of Snow Leopard on an iMac that needed its hard drive replaced. Not cool, but it's a bit late now. This thread isn't about doing piracy, it's about moving away from piracy. I want to put Lion or Mountain Lion on so I have better compatibility with a Windows Server environment. Can I upgrade from the pirated Snow Leopard to a legit Lion or ML? If so, (and obviously I'd backup first) how safe is it? Further, is the standard App Store Lion or ML app appropriate? Or do I need a different licence as it's not really an upgrade (although of course the iMac came with a version, so in a way we did have a copy)? Any help much appreciated - am happy to admit I'm fairly new to the Mac world. Thanks, K.