
Mac os mountain lion dmg how to#
But I have not found any instructions of how to create a bootable Mountain Lion installer under El Capitan. There are also instructions on how to create a bootable Mavericks or Yosemite installer under El Capitan. There are many instructions on how create a bootable Mountain Lion installer on a computer running Mountain Lion, a Mavericks installer on a Mavericks system up to an El Capitan installer under El Capitan. Trying to, you get a message that the copy of "Install OS X" is too old to be opened on this version of OS X. You need to make a bootable installer because the ML installer itself won't run under El Capitan. This requires that you have both the El Capitan installer as well as the Mountain Lion installer on your computer (at the paths indicated above, adjust the paths in the command if necessary) and that you have an HFS+ volume with the name 'Untitled' mounted (adjust the name in the command if necessary). Sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia -volume /Volumes/Untitled -applicationpath /Applications/Install\ OS\ X\ Mountain\ Lion.app -nointeraction If you ever wondered how to create a bootable OS X Mountain Lion installer under El Capitan, here is the Terminal command to do so:
