MacOS Monterey Won’t Install Onto Macs with Non-Apple HDD

I ran into this problem upgrading an old 15" MacBook Pro to an m.2 NVMe drive. Ultimately, I had to purchase an Apple SSD, install the OS so that the firmware would get applied, and then put the new SSD back into laptop.

Thank you for jogging my memory, Old Toad!

I had this same issue on a 2010 Mac Pro when I tried to upgrade it to High Sierra. That version required a firmware update as it introduced APFS. Mojave of course also had a firmware update.

The point being, when I tried to install High Sierra on a blank drive, as Richard-ZA is trying to do here with Monterey, the installer would just go in a loop of seemingly installing the firmware and OS, then boot back to the same OS I had started up to with nothing having been installed. Neither the firmware or the newer OS.

The solution was you had to upgrade the OS on the volume you started up to in order for it to work. Since I didn't want to lose the Sierra install before I could test High Sierra for software compatibility, I cloned the Sierra drive to the empty volume. I then started up to the cloned volume and ran the High Sierra upgrade. That finally applied the firmware and upgraded the clone to High Sierra.

Short version, when a firmware upgrade is required, it can't be done while trying to install the OS upgrade to an erased volume at the same time.

Is that true in all cases where a firmware upgrade exists? Probably not, but it did on the 2010 Mac Pro for High Sierra and Mojave, and is probably the case here.

During the final stages of installation process, Monterey checks the version of the firmware. If it's out of date, it puts a firmware installer on the boot drive's EFI partition and reboots the machine. In the next stage, the boot loader sees the firmware installer and tells Monterey to execute it as soon as it starts up. When executed, the firmware installer checks if the boot drive is an Apple drive, if so, it installs the firmware on the Machine and reboots the machine to finish the Monterey installation, if not, it spazzes out and aborts the installation with an error message stating the drive is unrecognized.

Unfortunately, this is a chicken or the egg situation where the Monterey can't install because the firmware is out of date, but the firmware can't be updated because the drive is unrecognized and can be only installed from Monterey. The official solution is to remove the third party drive and reinstall the original Apple drive and go through the install process. Once the firmware is upgraded, the original drive is removed and the third-party drive is reinstalled. The install process is repeated once again and this time, since the firmware is updated, it skips the firmware update stage.

Unfortunately, getting around swapping drives isn't a feasible option, at least not yet. There are open source EFI boot loaders available which replace the official boot loader. They spoof the machine's identification in order to bypass installer and system hardware checks. The amount of effort and time, however, in making these boot loaders work makes swapping drives a more practical solution.

The first time a Mac installs macOS 10.13, 10.14, 10.15, 11.x, and 12.x to either an internal or external drive, the macOS 10.13+ installer requires a working properly erased (i.e. partitioned & formatted) internal drive for use with macOS. The Monterey installer also appears to require an internal original Apple OEM SSD as an additional requirement. The internal drive does not need to have any files on the drive. The internal drive's only requirement is to be properly erased using Disk Utility as GUID partition and HFS+/APFS (depends on the installer) so that the macOS 10.13+ installer can place the Mac's system firmware updater onto the internal drive. When the installer reboots the Mac, the system firmware updater will be run to update the Mac's system firmware, then later finish the macOS installation & setup.

AFAIK, once the system firmware has been updated by the macOS installer, then that particular macOS installer no longer requires a working properly erased internal drive since the system firmware updater included in the macOS installer no longer needs to be run since the Mac's system firmware is already up to date.

The internal drive requirement seems to be dictated by the system firmware updater included in each macOS 10.13+ installers. The older pre-macOS 10.13 installers did not have this requirement (I don't believe the older macOS installers included a system firmware updater -- or at least did not include any hardware requirements -- I seem to recall reading that Apple only began including the system firmware updaters in the macOS installers beginning with 10.13 since Macs were not getting their firmware updated with the regular macOS patches). I believe it may be possible to pull the firmware updater from the macOS installer and manually update the Mac's firmware, but I've never had the time to investigate this option and probably will never have the time (I may not even have the necessary knowledge to pull it off -- plus I would need to risk bricking a Mac if I failed).

FYI, the earlier Apple SSDs in the older non-USB-C Macs would have the Apple name on them, but would have the manufacturer's initials on the actual model number shown in the System Profiler and other utilities (SM, SD, TS for Samsung, SanDisk, Toshiba), but the SSDs for the USB-C Macs now have only the Apple initials of "AP" on the SSD's model number.

Here we go. This finally explains it.

https://discussions.apple.com/thread/253316253

It isn't just an issue of having a third party drive. It's if the original Apple installed drive is missing. Which is why I had no problem installing Mojave or any other later OS release on my non-Apple external SSDs or hard drives. The original SSD in my 2018 Mini is there (has to be since it's soldered in), so what the other drives may be is irrelevant to installing an OS.

Which is what HWTech mentioned above:

The Monterey installer also appears to require an internal original Apple OEM SSD as an additional requirement.

No. The firmware must be installed while booted from an Apple drive. Without it you won't be able to install Monterey. You'll have to stay with Big Sur on that machine.

Give an Apple Authorized Service Provider  a call and see if they can update the EFI for you.

I looked around a bit, and it's a more common issue than you would think. The solution given at more than one site I visited is to disconnect anything from the Mac that doesn't need to be attached during the upgrade. No hubs. No external drives, even if they're turned off.

It may be possible to put OS X Monterrey on an external SDD, but the firmware in my 2015 MacBook Pro is not being updated on the machine to the current version with a new OWC SSC installed. OWC says put the old mac hd back in and upgrade the OS which will upgrade the computer firmware, then put their SSD Aurora Pro back in and install Monterrey on that hard drive. Catch-22, I don't have the original hard drive (because I updated it) and didn't expect Apple to not let the firmware of the machine update from that point forward. Infuriating.

Apple doesn't manufacture a lot of their own hardware, but the error message on the alert and the logs, combined with every post here makes it unequivocally clear--it's the drive! Period.

I've been a Apple developer and technician since the 80s and Apple frequently used common third-party drives and with the ROM identifying them as an Apple drive. In fact, you can still buy old SCSI drives with gigabytes of storage for cheap on eBay, but if it sports the Apple logo, meaning it has the ID, it will cost you a pretty penny even for tiny 160MB one. Why so much more? It's because you can't format third party drives with Apple's disk utilities. The only way around it is to use a third party disk utility program, or patch Apple's disk utilities to by bypass the ID check.

Oops! Sorry, I read your initial statement (twice!) and read it both times as your iMac doesn't qualify. Must wake up. 🙂

That said, I'm now not sure why it won't install. Other than drives for Catalina and forward must be formatted with a GUID partition map, and the volume must be APFS.

The last part I know isn't true. I have three different external SSDs (all purchased from Other World Computing), and had no issue installing Mojave, Catalina, Big Sur or Monterey on any of them.

Still doesn't help explain why Monterey is balking on your drive.

I've been a Apple developer and technician since the 80s and Apple frequently used common third-party drives and with the ROM identifying them as an Apple drive.

Yes, and it was that long ago, too, that Apple had drives just for their computers. They had their own floppy and CD drives, too. That type of setup hasn't been used in years. Like at least the past decade.

I put various drives in my 2010 Mac Pro. Just plain ol' hard drives purchased on Amazon, and an SSD from OWC. Nothing "Apple" about them. They worked the same as any other drive, including the original plain ol' Hitachi drive the Mac came with.

You simply can't apply almost 40 year old requirements to current Macs.

Apple still uses custom firmware for their drives. This has never changed.

In fact macOS is so particular about the SSDs used in a specific Apple computer, that using another original Apple OEM PCIe SSD from another model Mac may not work at all even if the SSD uses the exact same physical connector. I personally experienced this where an Apple OEM SSD from another different model Mac would not even boot an external macOS drive (full macOS or installer). The SSD worked perfectly fine using Linux (I was even able to install Linux to that SSD and boot Linux from that SSD).