Os X El Capitan Installer App Download

When the store is trying to download the OS X El Capitan installer app, it scans all your mounted drives to see if you already have the installer. If it finds an older El Capitan installer app (in my case I saved a backup copy on a separate volume to free up space on my startup drive), it will determine you're ineligible for download of the. To start the installation of El Capitan double click on the Install OS X El Capitan.app. The copy of the install app self deletes after installing El Capitan, so make sure you keep a copy of the InstallMacOSX.dmg if you need it in future, or you could just make a copy of the Install OS X El Capitan.app.

Bootable USB Installers for OS X Mavericks to Sierra

First, review this introductory article: Create a bootable installer for OS X Mavericks or Yosemite - Apple Support. Second, see this How To outline for creating a bootable El Capitan installer. Simply replace the Terminal command with the one from the preceding article by copying it into the Terminal window.

You will need an 8GB or larger USB flash drive that has been partitioned and formatted for use with OS X.

Drive Partition and Format

Os X Yosemite

Open Disk Utility in the Utilities folder.
After Disk Utility loads select the drive (out-dented entry with the mfgr.'s ID and size) from the side list.
Click on the Erase tab in the Disk Utility toolbar. Name the drive, 'MyVolume'. <---- IMPORTANT!
In the drop down panel set the partition scheme to GUID. Set the Format type to Mac OS Extended (Journaled.)
Click on the Apply button and wait for the Done button to activate. When it does click on it.
Quit Disk Utility.

Create Installer

Open the Terminal in the Utilities folder. Choose the appropriate command line (in red) depending upon what OS X installer you want. Paste that entire command line from below at the Terminal's prompt:

Command for macOS Sierra:

sudo /Applications/Install macOS Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyV --applicationpath /Applications/Install macOS Sierra.app

Command for El Capitan:

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

Command for Yosemite:

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

Command for Mavericks:

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

Os X El Capitan 10.12

Press RETURN. You will be asked for your admin password. It will not echo to the Terminal window. Then press RETURN again. Wait for the return of the Terminal prompt signifying the process has completed. It takes quite some time to finish. Be patient.

Oct 5, 2016 8:12 PM