this July 2017!! Unfortunately, I cannot upgrade, I need the older operating system for some applications. Hi, microsoft has deactivated Skype for older Mac operating systems like 10.6.8. Safe and fast downloads for Windows, Mac and Linux apps. Download latest (newest) and older versions of free software. Apple Mac OS X, Macintosh Operating System Versions: Mac OS X version 10.5.8 or a later version of Mac OS Note To verify that your computer meets these minimum requirements, on the Apple menu, click About This Mac.