Mac Os El Capitan Installer

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  • I am trying to upgrade an older iMac (2008) from OS 10.6.8 to El Capitan for a disabled client who really needs to use a Mac instead of a PC!
  • EveryMac says it can handle El Capitan if I upgrade RAM. It has 4GB now.
  • I have an Installer file from my own Mac (always keep them when I upgrade). I made a bootable flash installer that mounts and seems to have the proper files, but it won't show up on either Mac on restart holding option key; nor in the Startup Disk list. So, I figured writing to the flash drive must have failed.
  • I partitioned an external hard drive and redid this:

    'sudo /Applications/Install OS X El Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install OS X El Capitan.app'

  • It seems to work (again) in Finder AND it shows up as a boot option on restart (holding option key), but when I select Install OS X I get an error that the installer cannot be verified. I can't get it to work.
  • So, I figured my installer must have gone bad, even though I successfully upgraded my own Mac with it, and have since upgraded mine to Sierra.
  • Using the App Store I can get to El Capitan, but it will not allow me to download it on my Mac because the system is too new, and I don't want to download it to the old Mac because I want to use an external drive to do a clean install; not an upgrade on the old one.
  • Any advice?
Download mac os el capitan installerMac os x el capitan installer

IMAC (RETINA 5K, 27-INCH, LATE 2015), macOS Sierra (10.12.3)

  • Use the arrow keys to select Boot OS X Install from Install OS X El Capitan (It should be selected by default). Press the spacebar and select Boot Mac OS X in verbose mode. Verbose mode means that you'll be able to see exactly what's going on under the hood as OS X attempts to boot up its installer.
  • Sep 30, 2015 OS X El Capitan Installer. Official OS X El Capitan Installer from the Mac App Store. Un-archive the zip archive and you will get the app Installer. A bootable ISO or bootable USB can be made from this installer. Instructions on how to do that are on the Internet/Youtube.
Mac

As explained here, OS X 10.11 'El Capitan' fails to install because it is too old (the technical reason being that the signing certificate is no longer valid). But you can trick the OS X installer into thinking that it is 2017 and it will happily run without any errors.

Mac Os El Capitan Installer App Download

Posted on Feb 28, 2017 9:53 PM

Mac Os Sierra

  • I am trying to upgrade an older iMac (2008) from OS 10.6.8 to El Capitan for a disabled client who really needs to use a Mac instead of a PC!
  • EveryMac says it can handle El Capitan if I upgrade RAM. It has 4GB now.
  • I have an Installer file from my own Mac (always keep them when I upgrade). I made a bootable flash installer that mounts and seems to have the proper files, but it won't show up on either Mac on restart holding option key; nor in the Startup Disk list. So, I figured writing to the flash drive must have failed.
  • I partitioned an external hard drive and redid this:

    'sudo /Applications/Install OS X El Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install OS X El Capitan.app'

  • It seems to work (again) in Finder AND it shows up as a boot option on restart (holding option key), but when I select Install OS X I get an error that the installer cannot be verified. I can't get it to work.
  • So, I figured my installer must have gone bad, even though I successfully upgraded my own Mac with it, and have since upgraded mine to Sierra.
  • Using the App Store I can get to El Capitan, but it will not allow me to download it on my Mac because the system is too new, and I don't want to download it to the old Mac because I want to use an external drive to do a clean install; not an upgrade on the old one.
  • Any advice?

Mac Os El Capitan Download

IMAC (RETINA 5K, 27-INCH, LATE 2015), macOS Sierra (10.12.3)

Mac Os El Capitan Installer App

Posted on Feb 28, 2017 9:53 PM

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