My friend got a new MacBook Pro from office, later on he resigned and in a hurry erased the "Macintosh HD", now we are trying to install Mojave using Bootable USB but it won't allow because "External Boot" is not allowed, also when we try to access "Startup Security Utility" it shows an error saying no administrator was found, so we can't enable "Allow booting from external media". Somehow online installation from recovery mode is also not working and throws 202 error at the end. Is there any luck?

  • Hey there, Welcome to Apple.SE! I don't have administrator account on my mac is it helpful?
    – anki
    Jul 11, 2019 at 18:52
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    The system was probably a part of a managed system and needs to be removed from that system. Presumably by their former workplace IT folks. Jul 11, 2019 at 18:54
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    @ankiiiiiii thanks! but as I mentioned there is no OS on MacBook right now, so how would it boot to "Single User Mode"? Or will it?
    – Hadi
    Jul 11, 2019 at 18:55
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    @SteveChambers He was given boxed pack MacBook Pro, so he's the first user.
    – Hadi
    Jul 11, 2019 at 18:56

6 Answers 6


I had to boot into recovery mode and reinstall High Sierra (the initial shipped version of macOS). Installing HS gave an administrator account. With the administrator account I was able to allow booting from any external device and finally booted from mac USB stick macOS mojave. After that I could remove HS.

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    Just did the same thing, in my case the default was Mojave and I installed Monterey from external disk. Had to then re-install Monterey again (so 3 installs in total) from recovery after creating a temp admin account, re-enabling external protection and wiping to remove the temporary admin account. Bonus: reset the NVRAM (option, command, R, P on startup) to give a completely clean startup to the "welcome" screen for the next user. Nov 1, 2021 at 7:48

I just came into the same situation. But I was lucky enough to workaround it last night. It took me 2 nights searching around to figure out what to do. Here's what you need:

*. A functioning Mac(Better without a T2 chip), mine is the 2014 Mac Mini.

*. An SSD for a fresh install.

*. Create a bootable macOS USB drive.

I will make it short. You could search for tutorials if you don't know what to do for a certain step.

  1. Plug in both SSD and bootable USB drive(with Mojave installer).
  2. Reboot your mac and press Command + R.
  3. Install a fresh Mojave on your SSD, and stop when you see the welcome screen where it asks you to select your country.
  4. Power off and unplug the SSD off your functioning Mac.
  5. Plug your SSD onto your MBP and turn it on.
  6. Press Command + R and enter the recovery mode.
  7. Disk Utilities -> Restore. Here select your SSD and it will copy your SSD's files onto your MBP. And then you can unplug your SSD.
  8. You could try select your internal drive as start up disk but it doesn't let you to. So reboot your MBP. And press Command + R. In my case it failed to boot the macOS and it just reboot into the recovery mode again.

  9. Select Install Mojave. After a couple of minutes, your screen turns black and it reboots.

  10. You will see the lovely Welcome screen again.
  • Great answer! worked like a charm when i thought I was dead in the water cuz i had already erased my Macintosh HD. After step 7 i was able to change my startup disk and it booted up! Thank you
    – ganta
    Dec 30, 2019 at 6:01
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    Downvoted: As described, External Boot is not allowed, so steps 2+3 don't work. Cmd+R brings up a message that External Boot is not allowed. I'm working through the same problem right now.
    – Drew
    Nov 23, 2020 at 23:18
  • Hi, Drew. You need another functioning Mac(models without T2 chip) or someone to help install a fresh OSX for you(Stop at welcome screen) and start from #6. And then you use the Disk Utilites to clone the whole fresh system to your Mac. It looks like that the T2 security chip blocks external disk boot or installation. Nov 24, 2020 at 1:58
  • Hi. Just trying to work out what the "TL;DR" is on this answer.. Essentially, is it simply installing macOS on a different Mac (without the same boot restrictions) and then swapping the disks?
    – mwfearnley
    Apr 13 at 9:28
  • Hi, yes. You just need a fresh install before setting up personal information on a disk. So that the T2 chip won't block you again. Apr 13 at 10:15

I had a similar issue with my 2018 Mini: I had to delete the .AppleSetupDone file and run the "Welcome to Mac" routine, creating a new admin user there before I could alter SecureBoot, even though the disk had been imaged with an admin user.

Peter Thorn's answer here gets to the exact cause of the problem and provides the solution for a working Mac that has MacOS installed.

If you don't have MacOs installed, you could try booting it in Target Mode from another Mac, which I understand bypasses the Secure Boot! (Though if the drive is encrypted, you'll need the password, unless you're wiping it anyway.)

Alternatively, take it to an Apple Store. The SecureBoot settings can't be changed unless there is a valid admin user, so you can't boot to an external. Recovery is another option, but you say that's not working.

PS. I'd love to work somewhere where you get to keep your laptop when you resign!

  • First part doesn't help for wiped systems as in this case (and my case). Target Mode may be worth trying. Darkwonder's response below, which for some reason got the least votes (zero), is the most appropriate. PS When I left my job at a small company after 3 years, I got to keep my laptop..
    – Drew
    Nov 23, 2020 at 23:21

To my experience, it is a question of Secure Tokens, if it doesn't accept the admin even though it has the shipped (old) macOS installed from the recovery partition.

Even though you have created an admin account, you need it to have a Secure Token and update the preboot, for the recovery partition to accept it.

I did the following (when logged in as the local admin account) (both commands run in Terminal):

sysadminctl interactive -secureTokenOn [admin user shortname] -password -

(you will be asked to authenticate).

diskutil apfs updatePreboot /

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    Yes, this is the best answer. Gets to the nub of the problem and shows the solution.
    – benwiggy
    Jan 7, 2020 at 13:18
  • It doesn't have the shipped macOS installed - the OP (and me) are trying to install an OS. And there is no created admin account - the boot drive is wiped.
    – Drew
    Nov 23, 2020 at 23:20
  • diskutil: UpdatePreboot: Exiting Update Preboot operation with overall error=(ZeroMeansSuccess)=-69567 Error: -69567: An Open Directory user database record is missing a data field required by EFI Apr 16, 2021 at 22:06
  • To fix error above read this and create "recovery key and do not use icloud": twocanoes.com/… Apr 16, 2021 at 22:09
  • To fix an error turning on FileVault temporarily: add a full name, like "Adam Minister" to your account. Apr 16, 2021 at 22:11

I managed to get around this by using Disk Utility (from recovery mode) to "restore" my internal drive with the image on my external bootable drive. Voila, your bootable drive is no longer "external" and you can boot from it. You'll probably want to create a separate partition on your internal drive for the bootable partition to install to; ideally your second partition is the installer so that you can delete it later without the "you can't remove the first volume on the disk" error.


I was able to get to recovery mode by starting to select a start up disk and then quitting with Command - Q. Took me back to recovery mode and I was able to install Mojave on the internal drive.

(I had this exact issue and foolishly wiped the drive not realizing that the security was set to only internal drives.)

William Tong’s answer is great, but similar to commenter, I could still not boot into recovery with the blank Mojave’s SSD. It would prompt that it couldn’t boot from external drive and to choose a startup disk or restart.

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    – fsb
    Aug 24, 2021 at 13:29

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