I still have my 2008 MacBook Pro, running OS-10.7.5. In Bootcamp (the alternate boot) I have Windows XP. Both operating systems are as updated as they can be. Long ago I was running Parallels on this machine, and I have legacy licenses for Parallels version 5 and version 10. I'm pretty sure it was Parallels version 5 that I was using long ago. I downloaded version 5 and tried to install it. The installation error message said something to the effect that an upgraded Mac operating system would be necessary. Is there a library where I can find an even earlier version of Parallels that my machine will accept? Any other ideas?