I'd like to factory reset my mac (which is running El Capitan 10.11.6), while also updating the operating system. Here's what I've done (i.e. steps from this website) in order to create a bootable installer:

Downloaded the Mojave installer from app store

used sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

When I do this, I get the error message "To use this tool, you must download the macOS installer application on a Mac with 10.12.5 or later, or El Capitan 10.11.6. For more information, please see the following: https://support.apple.com/kb/HT201372"

How can I update the operating system while also doing a factory reset? Thanks in advance.

  • 2
    Have you tried the shareware (free) utility diskmakerx.com. I have never had a problem with this. AND it involves less typing... ;-) – Steve Chambers Sep 3 '19 at 13:00
  • How big is the installer you downloaded? If it's only the stub, you need the complete installer before using createinstallmedia. – Marc Wilson Sep 3 '19 at 14:26
  • @MarcWilson, I'm sorry, but what do you mean by a stub? I thought I did have the whole installer, since I downloaded it from the app store. Thank you! – Lisa Sep 3 '19 at 17:29
  • 1
    If it's only 22mb, it's the stub, and it downloads what it needs while it installs. If it's 6gb, it's the full installer. – Marc Wilson Sep 3 '19 at 18:12
  • Oh I see. Yes it's probably the stub then, I'd guess. How do I access the full installer? – Lisa Sep 4 '19 at 13:03

I think the documentation saying MacOS 10.11.6 is wrong as I can't figure how to run that as well. You may need to have a friend run the installer and send you the USB drive with bootable media or perhaps try one last time to reinstall 10.11.6 from this link:

Sometimes re-installing the same combo updater fixes edge cases or some bit rot / rare damage to existing files. Just because your OS says 10.11.6 doesn't mean everything is in perfect running order.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .