Most of the time, you can re-download the current version of macOS via the Mac App Store, and older ones via these links:
Dan Frakes wrote a guide to creating OS X 10.11 El Capitan install disks for Macworld. There is one qualification to all this. Apple won’t allow a newer Mac to download versions of OS X that aren’t compatible with that Mac, so on a 27-inch iMac with Retina display, for instance, the App Store app refuses to let you download Mac OS X 10.7 Lion. How to Download and Install Mac OS X 10.11 El Capitan Mac OS X El Capitan can be downloaded directly from the Apple website. The Beta version of the OS is available but the final version will be made available towards the Autumn season of 2015 as speculated by many Apple users.
However, I’ve run into a situation several times where the Software Update mechanism simply refuses to initiate a download:
Thankfully, macOS installers can be downloaded via Terminal in macOS Catalina. This command will download the most recent version of macOS, depositing it in your Applications folder:
![Installer Installer](/uploads/1/2/4/6/124624739/267717418.png)
softwareupdate --fetch-full-installer
![Download Download](/uploads/1/2/4/6/124624739/553963190.jpg)
The
softwareupdate
command has some neat tricks up its sleeve, as pointed out by Armin Briegel: The
--fetch-full-installer
flag has a sub-flag: --full-installer-version
which allows you to download a specific version. During my testing in the Catalina beta version I was able to download 10.15, 10.14.6, 10.14.5, and 10.13.6. I was not able to test if 10.13.6 would download the hardware specific build of 10.13.6 for the 2018 MacBook Pro, since I do not have that hardware.
So, to pull 10.13.6 down, you’d use:
softwareupdate --fetch-full-installer --full-installer-version 10.13.6
Download Mac Os X 10.11 Installer.iso
I wish Apple would just have a support document up with direct downloads for all of this stuff, but this tool is not a bad alternative.
Download Mac Os 10.11 Installer Installer
Update: Don’t miss this documentation from JAMF for more on the subject.