1. Install Mac Os El Capitan
2. Install Mac Os El Capitan On Unsupported Mac
3. Install Macos El Capitan From Usb
4. How To Install Mac Os El Capitan

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.

Click on the download link that shows up, and enter the personal redemption code given to you. Open the downloaded Mac OS X El Capitan software and preview the file in the Applications folder. Click “Continue” and then select “Agree”. Click on “Install” and then enter your admin password. I was able to successfully install El Capitan, following Charlee78's suggestion to set date at Terminal on OSX Recovery mode before continuing with OSX installation. Download El Capitan from another early 2008 iMac, compatible only until El Capitan. Made a bootable El Capitan USB. 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 prior to installing and moving it to. How to Perform a Clean Install of OS X El Capitan. OS X El Capitan (OS X 10.11) offers two installation methods. This guide focuses on the 'clean install' method. When you install El Capitan on your current startup drive with the clean install method, you erase everything on the drive. That includes OS X, your user data, and personal files.

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. Ttsystem file missing. Make sure you’ve attach another disk which can be overwritten by the installer. In this example its named „MyBlankUSBDrive“:

Install Mac Os El Capitan

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.

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

El Capitan Installer cannot be verified

Install Mac Os El Capitan On Unsupported Mac

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

Install Macos El Capitan From Usb

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.

How To Install Mac Os El Capitan

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.