Few days ago I successfully installed Mountain Lion 10.8.4 on a late 2007 MacBook. Thought it would solve my issues with my phone no longer syncing in iTunes. Turns out iOS 10 requires iTunes 12.5 and up, which is supported only on Yosemite and later OS's, so I'm going up to that. Now I'm trying to update from ML to Mavericks using the newest version of MacPostFactor. I think my question is simple. The initial installation in MCPF where it creates the installer goes successfully. (By the way I'm NOT installing onto a USB, but can try it if you think it will help. I'm installing to a 2nd partition of my main HD.) The software is then supposed to reboot my computer, which it does, and the OSXHACKERS logo is supposed to appear, then when it boots I'm supposed to click a few things to finish the process. However, the OSXHACKERS logo does not appear, and it simply boots back into Mountain Lion. It does show my Mavericks (named MAV) partition under devices in the Finder, and it has three folders on it (Library, System and tmp). That's it. Does anybody have a suggestion? Something seems to be going wrong at the end of the installation process. Should I try an older version of the software? I read they have some bugs... Another question, I figured it's better to try Mavericks first before trying to install Yosemite (it runs the version of iTunes i need) but do you think I should just skip 10.9 and go straight to Yosemite? I'd still appreciate suggestions as this same problem may well happen when installing Yosemite if that's the case.