Create External Monterey Bootable Installer using Tahoe

Only if your Mac is compatible with Monterey.

If your Mac is also compatible with Monterey, then you can use the instructions in the following Apple article to create a bootable USB installer......there is a link within this article to download various macOS installers:

Create a bootable installer for macOS - Apple Support

How to download and install macOS - Apple Support

Otherwise you will need access to another Mac generally a model Late-2013 to mid-2022 (Intel or M-series is Ok)....you can use the information in the following article to confirm which versions of macOS are compatible with various Apple hardware since those model years are just generalizations (2015 to mid-2022 models should all be compatible):

https://eshop.macsales.com/guides/Mac_OS_X_Compatibility

You can also boot into Internet Recovery Mode (Command + Option + R) on an Intel Mac to access the most recent online macOS installer that is compatible with the Mac....version varies depending on the model of the Mac.

How to reinstall macOS - Apple Support

If your daughter's laptop is not booting normally or into Safe Mode, then you may have to start with whatever version of macOS you can get through Recovery Mode....then later create a bootable macOS Monterey USB installer to upgrade or downgrade the system (yes, multiple steps, but may be the only option if you have no access to other Macs compatible with Monterey).

FYI, it really helps if you provide the exact model of both Macs when asking for assistance since this information is usually needed for the majority of issues. You can get the exact model by clicking the Apple menu & selecting "About this Mac". If the Mac is unable to boot normally (or Safe Mode), then you can use the system serial number on the check coverage page to get that information (don't post the serial number on the forum since it is considered personal information):

View Coverage - AppleCare & Warranty

> macOS 12 Monterey can be downloaded from the App Store here:

https://apps.apple.com/us/app/macos-monterey/id1576738294

However, whatever Mac you have to create a bootable installer from this download must itself qualify to run the Monterey OS. For example, a brand new MacBook Pro M5 that ships with macOS 26 Tahoe cannot create a bootable installer for macOS 12 Monterey because Monterey predates the release of that MBP, therefore doesn't qualify to run that older OS and cannot create a bootable installer for it.

An appropriate Mac to create a macOS 12 Monterey bootable installer would generally be one released between 2015 and 2022. If you have one in mind please post the make and model and someone here can confirm that it qualifies to run Monterey.

Otherwise, unless there is some problem that prevents a normal reinstall of the OS on your daughter's MBA, then you should use the Reinstall macOS from Recovery option. Reinstall macOS - Apple Support

BlueberryLover wrote:

My curiosity got the better of me. The screenshot below is the error that the Monterey installer throws when run on a newer version of macOS (I used Sequoia). I believe this is what people are referring to when they say that you can't use a newer macOS to install an older one. The workaround, if one can call it that, is to create a bootable installer.

Creating a bootable installer using a M-series Mac did not work on my Intel (i5) Mac mini (2018). The Startup Manager never appeared after booting with the Option key pressed. I suspect that this is related to the T2 security chip in this machine. Other models may not exhibit this behaviour.

I eventually found a solution which involves adding a step to Apple's procedure using Terminal. With this step, the bootable installer worked as expected (as it would have if the installer had been created on the Mac mini running Monterey).

cd /Applications/Install\ macOS\ Monterey.app/Contents/Resources/

sudo codesign -s - -f createinstallmedia

sudo createinstallmedia --volume /Volumes/MyVolume

To prove to myself that the modified procedure actually resolved the issue, I carefully recreated the bootable installer using my M2 Mac mini (2023) strictly according to Apple's documented procedure. Once again, the Startup Manager did not appear.

Using the Disk Utility, it is possible to create an ISO or DMG image of the installer. However, I'm not sure of the procedure to recover that image back onto a USB key.

https://discussions.apple.com/content/attachment/3db01612-b21d-42cb-a44b-77e0ac2dbf66

- Pie Lover

With a bit of persistence, I was able to use a DMG disk image of a USB bootable installer on a system on an Intel Mac (running Monterey) and restore the disk image on a M2 Mac (running Sequoia). The Disk Utility restore function didn't work as expected but I was able to find an alternative – the Terminal ASR command successfully restored the disk image but took a somewhat surprisingly long time to complete.

This process allows bootable installers to be archived for future use rather than rely on multiple USB keys which, in my case, tend to get lost or overwritten.

- Pie Lover

ThankYouForAnyHelp wrote:

thanks for your time Gents, but the only option available to revive the MacBook Air is an external bootable installer. No other options are available. The latest MACOS it can run is Monterey

This implies it is an Intel Mac so use Internet Recovery Mode by using Command + Option + R to attempt to access the online macOS Monterey installer. Even if it only gives you the online installer for the version of macOS which originally shipped with the Mac from the factory...you can use that as a starting point, either for a clean install or to install to an external USB drive where you can then access the Monterey installer.

and my question is how can I create an external bootable installer using my MacBook Pro running Tahoe.

And I explained it in my previous post. You need access to another Mac which is also compatible with Monterey (the other Mac can currently be running any version of macOS). I even provided an article which can help you identify various Mac models that are compatible with Monterey (you do need to look at each type of Mac).

I can understand the problems if I was using an older machine to update a newer one..... but surely there's no problem using a new machine to create an installation drive for an older one?

Only if the Mac newer than the old Mac is still compatible with the OS in question. This has been the way it has been for all iterations of OS X/macOS from v10.1 to 10.15 & 11.x+. Nothing new here.

So it's as I feared then.... for some reason Apple won't allow this for their customers.

I do agree that Apple doesn't make it easy, but Apple doesn't care about old outdated hardware & software. Apple is only looking forward....so much so, that Apple has forgotten & deviated from a lot of good things from the days of old. It is irrelevant anyway since Apple computers & macOS are moving more & more to how iPhones/iPads work. That should tell you everything you need to know.

Dear oh dear. Oh well, thanks for your time anyway 🙏

I have given other options, but I suspect we are missing some critical information since you have seemed to ignore those other options. You can still get macOS Monterey installer even using your daughter's "broken" MBAir assuming the laptop does not have a hardware issue. It may not be an immediate & direct way to Monterey, but you have enough to get there with just your daughter's "broken" laptop if the hardware is good.

You only get out what you are willing to put into an endeavor. I think you are too focused on a USB installer & are missing the other options to get there.

If you provided the exact model of the "broken" laptop, then it would have allowed us to know if there were other options. Since you have a MBAir which can only upgrade to macOS Monterey, this implies you have either the 2015 or 2017 model. This means the laptop is also compatible with macOS 10.11 El Capitan. If Internet Recovery Mode doesn't work or is not an option for some reason unknown to us here, then you can generally use another Mac model from 2008 to 2015 to create a bootable macOS El Capitan USB installer, then upgrade to Monterey (either on internal SSD or external).

If you have any questions about a particular method, I will be glad to clarify & assist. You just need to provide more details about the problems your daughter's MBAir is having that requires a macOS Monterey USB installer.

If this is too much for you (nothing wrong with that), then you should take the laptop to a local Apple specialist to assist you. An Apple Store is unlikely to assist you for such an old system, but an AASP might, or maybe you can find a local macOS specialist...any local Mac user groups?

My curiosity got the better of me. The screenshot below is the error that the Monterey installer throws when run on a newer version of macOS (I used Sequoia). I believe this is what people are referring to when they say that you can't use a newer macOS to install an older one. The workaround, if one can call it that, is to create a bootable installer.

Creating a bootable installer using a M-series Mac did not work on my Intel (i5) Mac mini (2018). The Startup Manager never appeared after booting with the Option key pressed. I suspect that this is related to the T2 security chip in this machine. Other models may not exhibit this behaviour.

I eventually found a solution which involves adding a step to Apple's procedure using Terminal. With this step, the bootable installer worked as expected (as it would have if the installer had been created on the Mac mini running Monterey).

cd /Applications/Install\ macOS\ Monterey.app/Contents/Resources/
sudo codesign -s - -f createinstallmedia
sudo createinstallmedia --volume /Volumes/MyVolume

To prove to myself that the modified procedure actually resolved the issue, I carefully recreated the bootable installer using my M2 Mac mini (2023) strictly according to Apple's documented procedure. Once again, the Startup Manager did not appear.

Using the Disk Utility, it is possible to create an ISO or DMG image of the installer. However, I'm not sure of the procedure to recover that image back onto a USB key. Hopefully, this will be documented in the User Tip that HWTech is working on.

- Pie Lover

The Terminal commands to create various bootable USB installer drives is here:

Create a bootable installer for macOS - Apple Support

They all expect the OS image to be in the Applications folder, as shown here (randomly chose Monterey).

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

The back slashes are so the OS understands there are spaces in the name, and they are not command line switches. So /Install\ macOS\ Monterey.app is really Install macOS Monterey.app in the Applications folder.

You can put the image anywhere you want, but you then have to modify the command to find it. If on your desktop, then it would be:

sudo /~Desktop/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Lastly, MyVolume needs to be replaced with whatever the name of your USB stick is. Personally, I always name the USB stick something very simple, like a . Then the command is:

sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia --volume /Volumes/a

As noted previously, it is not possible to create a USB bootable installer on a Mac that cannot run the version of macOS in question.

BlueberryLover wrote:

Thanks for the detailed reply. I realize that and have actually used precisely that procedure many times before. However, the documented procedure is missing a step if the user is creating a bootable installer on an M-series machine to be run on an Intel machine. By the way, the terminal command that I mentioned is only valid if the default directory is set to the one you indicated (for Monterey):

cd /Applications/Install\ macOS\ Monterey.app/Contents/Resources/

sudo codesign -s - -f createinstallmedia

sudo createinstallmedia --volume /Volumes/MyVolume

The extra step allows the bootable installer USB key to be selected (after pressing the Option key on an Intel machine while booting). I was able to select the installer but didn't go so far as to reinstall Monterey on my Intel (i5) Mac mini (2018).

I only had to follow Apple's instructions when I created a bootable macOS USB installers on my M2 Mac with macOS 13.x Ventura. No problems booting the installer on either Intel or M-series Macs. I would not expect this to change with later or updated versions of installers.

I would not expect the version of macOS on the host Mac to make a difference since it is the "createinstallmedia" utility contained with each macOS installer does all the work.

The USB sticks or other drives used may be the problem since Apple hardware & macOS can be very particular about the drives used for booting.

The only time I can think such extra commands may be needed is when the macOS USB installer is created using some other types of hacks usually on unsupported systems.

HWTech is writing a step-by-step user tip that should address the case that I mentioned above.

It may not be what you are expecting. My tip will only be a slight variation & enhancement on Apple's existing instructions. A compatible host Mac will still be needed initially, but once completed the resulting installer image can be pushed onto a USB stick using any computer or OS. It is more about archiving the finished product so when it is needed any host computer & OS can be used.

Trying to create a bootable macOS USB installer using any host computer or OS is problematic since Apple has been known to significantly change the structure & packaging of the older .pkg extractors in the DMG files for the 10.7-10.12 installers and sometimes even the later "Install macOS <OS-Name>" apps downloaded from the App Store links.

It is just a continually moving target. This is why any attempts at using an unsupported host computer & OS is doomed to fail since Apple doesn't care about standardizing on the format as they have the designs & tools to keep up with their own changes with their seemingly complex, chaotic, and mysterious packaging which is likely based on how they build the various individual components.

BlueberryLover wrote:

Another alternative is to find a friend or neighbour to create the bootable installer. For example, I have an Intel (i5) Mac mini (2018) currently running Monterey 12.7.4 which would do the job. I was wondering if it is possible to create a disk image of the Monterey installer (on a compatible machine) which could then be used to create a USB installer on a newer Mac/macOS. I realize that this might not be possible because of checks at boot time.

I've actually been in the process of writing a User Tip to help people archive bootable macOS USB installers so that once created, they can be pushed out to a USB stick using any computer or OS. I've written a rough draft, but still need to test it out & make the instructions neater. I'll see if I can work on it this weekend. The process is very simple, but writing it up so someone that is not very computer literate is a bit of a challenge (I try to make things as accessible to everyone as possible).

I just created a bootable installer for macOS Monterey 12.7.4 using an M2 Mac mini running macOS Sequoia 15.7.1

Sorry if I missed something, but Isn't this what the original poster was looking for? Of course, the actually installation must be performed on a Mac that is compatible with Monterey (such as a Mac mini (2018) in my case).

BTW, once installed, the usual update mechanism will be needed to update to the final version of Monterey (12.7.6).

- Pie Lover

I tested the Monterey bootable installer that I had created using an M2 Mac mini. To my surprise, the Mac mini (2018) did not recognize the USB key installer as a startup device. Based on this test, I conclude that this approach does not work. I should also note that I was able to mount the bootable installer key using Recovery but again could not specify the installer as a startup device.

My assumption is that this restriction is related to security settings, however, I did not experiment to see if I could get it to work.

- Pie Lover

BlueberryLover wrote:

I should also note that I was able to mount the bootable installer key using Recovery but again could not specify the installer as a startup device.

This has never worked. The Startup Disk utility in macOS & Recovery Mode won't allow you to select the bootable macOS USB installer since you will only need to boot from it one time....no sense configuring the system to boot from a volume that will be non-existent after the upgrade is complete.

You can only see & select the bootable macOS USB installer at the Apple boot picker menu screen which on Intel Macs is accessed by holding the Option key immediately after the startup chime, or on an M-series Mac by holding the power button unto "Loading Startup Options" is shown on the screen.

Thanks for the detailed reply. I realize that and have actually used precisely that procedure many times before. However, the documented procedure is missing a step if the user is creating a bootable installer on an M-series machine to be run on an Intel machine. By the way, the terminal command that I mentioned is only valid if the default directory is set to the one you indicated (for Monterey):

cd /Applications/Install\ macOS\ Monterey.app/Contents/Resources/
sudo codesign -s - -f createinstallmedia
sudo createinstallmedia --volume /Volumes/MyVolume

The extra step allows the bootable installer USB key to be selected (after pressing the Option key on an Intel machine while booting). I was able to select the installer but didn't go so far as to reinstall Monterey on my Intel (i5) Mac mini (2018).

HWTech is writing a step-by-step user tip that should address the case that I mentioned above.

- Pie Lover