I have bought and downloaded OS X mountain lion with no problems until the end. I click on it to install the software when i get a message saying that the version I have is too old for my mac and I am not computer person and I have no clue what to do next.
MacBook Air
What year is your computer? You can't install an OS older than the one that came with your computer.
Why do you want to install Mountain Lion.anyway?
What OS X version is currently on your Mac? Mavericks? Yosemite? If either of those are your current OS then this is why you can't install ML. You can't install an older OS on top of a newer one.
Also, if your Mac came pre-installed with either OS X Mavericks or Yosemite, you won't be able to install ML.
Back up your system first.
If your Install OS X Mountain Lion.app file is still in your /Applications folder, see if you can use an external USB drive and install ML onto that.
Or..... follow this link to create an ML USB thumb drive installer. Then you can add a 2nd partition to your Mac, restart with the ML installer and try installing to the 2nd partition.
As Eric Root says, you cannot install an older version of Mac OS X on a computer than what was originally shipped with the Mac.
If for some reason you need to run Mountain Lion (perhaps you need to run some software that only runs via Mountain Lion), then you can install Mountain Lion in a virtual machine, such as VMware Fusion, Parallels, or VirtualBox.
its saying the os x mountain lion is too old for my mac...what can i do to install it?
