El Capitan Installer App

The El Capitan installer is downloaded to the /Applications folder, with the file name 'Install OS X El Capitan.' If you've installed El Capitan and want to create a bootable installer, re-download the installer from Apple. 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. NOTE: If you get a damaged message when launching, no need to worry.

I’m trying to sell a 2009 MacbookPro. It’s the model MacbookPro5.5 and Apple supports macOS El Capitan 10.11 as latest available version.

I’ve wiped all data from the installed SSD and had to boot from an external disk. Now I’ve got two problems:

  1. I’ve only got a Mac with Big Sur and Apple Silicon. I cannot use the package installer from the download provided by Apple to create the installer App for El Capitan. However, I need access to the installer so that I’m able to use the createinstallmedia command.
  2. The 2009 MacbookPro is already wiped and has only access to the recovery mode. You cannot execute the package installer in Recovery Mode to extract the media.

Luckily I’ve found this blog post from Chris Warrick who explained how to extract the installer App from the package:

  1. Attach an external Disk which contains the downloaded pkg from Apple. You’ll need enough space on that Disk to extract the pkg and it needs to be writeable
  2. Open the Terminal from inside the Recovery Mode
  3. Go to the mounted volume
  4. Extract the package:

Now we can try to create the install media from the installer app. Make sure you’ve attach another disk which can be overwritten by the installer. In this example its named “MyBlankUSBDrive”:

The InstallESD.dmg image is missing, which we’ll need to add to the right location:

Now we’ll have a valid installation medium which can be used to start the installer from. You can reboot from that disk and should be able to install El Capitan.

Download El Capitan Installer App Store

However, I’ve encountered another annoying issue which caused the installer to fail:

El Capitan Installer cannot be verified

El capitan full download

Oh great… On to the next commands you can try from the Terminal inside the Recovery OS:

  1. installer -pkg /Volumes/Mac OS X Install DVD/Packages/OSInstall.mpkg -target /Volumes/'XXX' where XXX is the name of the disk you’re installing to.
  2. Wait for the installation to say it’s complete. You will not see any sort of progress display.

Great, you’ve got El Capitan installed! Apple had some issues with certificates and people found a way to either use the above commands for installation or you’ll have to tinker with your Macs time settings so that the signature is valid again. I would have expected that Apple resigned all installers so I wouldn’t have to use these commands at all but doesn’t look like they did.

El Capitan Installer App

To get the latest features and maintain the security, stability, compatibility, and performance of your Mac, it's important to keep your software up to date. Apple recommends that you always use the latest macOS that is compatible with your Mac.

Learn how to upgrade to macOS Big Sur, the latest version of macOS.

Check compatibility

The version of macOS that came with your Mac is the earliest version it can use. For example, if your Mac came with macOS Big Sur, it will not accept installation of macOS Catalina or earlier.

If a macOS can't be used on your Mac, the App Store or installer will let you know. For example, it might say that it's not compatible with this device or is too old to be opened on this version of macOS. To confirm compatibility before downloading, check the minimum hardware requirements:

Download El Capitan Installer App

  • macOS Catalina 10.15 hardware requirements
  • macOS Mojave 10.14 hardware requirements
  • macOS High Sierra 10.13 hardware requirements
  • macOS Sierra 10.12 hardware requirements
  • OS X El Capitan 10.11 hardware requirements
  • OS X Yosemite 10.10 hardware requirements

Download macOS using Safari on your Mac

Safari uses these links to find the old installers in the App Store. After downloading from the App Store, the installer opens automatically.

  • macOS Catalina 10.15 can upgrade Mojave, High Sierra, Sierra, El Capitan, Yosemite, Mavericks
  • macOS Mojave 10.14 can upgrade High Sierra, Sierra, El Capitan, Yosemite, Mavericks, Mountain Lion
  • macOS High Sierra 10.13 can upgrade Sierra, El Capitan, Yosemite, Mavericks, Mountain Lion

El Capitan Installer App Store

Safari downloads the following older installers as a disk image named InstallOS.dmg or InstallMacOSX.dmg. Open the disk image, then open the .pkg installer inside the disk image. It installs an app named Install [Version Name]. Open that app from your Applications folder to begin installing the operating system.

El Capitan Os X Download

  • macOS Sierra 10.12 can upgrade El Capitan, Yosemite, Mavericks, Mountain Lion, or Lion
  • OS X El Capitan 10.11 can upgrade Yosemite, Mavericks, Mountain Lion, Lion, or Snow Leopard
  • OS X Yosemite 10.10can upgrade Mavericks, Mountain Lion, Lion, or Snow Leopard