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Reinstall Monterey - Can't Do It - Says Cannot Be Downgraded

Am trying to reinstall Monterey on an external SSD boot drive. I downloaded the latest from the App Store. Cannot reinstall because it says Monterey cannot be downgraded.


I suspect I have installed all updates to Monterey. And the downloadable Monterey is not up to date?


What can I do?

iMac 27″ 5K, macOS 12.6

Posted on Jun 20, 2023 9:48 AM

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Question marked as Top-ranking reply

Posted on Jun 22, 2023 6:16 AM

I gave up. I reformatted, reinstalled the MacOS and recovered from TimeMachine.


BTW, make a USB boot stick and do it now. For whatever reason, I could not install the Mac OS via MacOS Recovery after formatting the drive. It would get to the end and say 'An Error Has Occurred'.

5 replies

Jun 20, 2023 12:17 PM in response to ku4hx

Used on this same Mac.


I can’t reinstall Monterey from a USB installer drive I created nor when booting off the internal drive with Monterey that I just downloaded from Apple.


When trying from MacOS recovery, that drive is grayed out. When I click on it, I get the message ‘The operation couldn't be completed. (com.apple.BuildInfo.preflight.error error 21.)’


When I try reinstalling from the app after booting from the internal drive, I get the ‘cannot be downgraded’ message.


When I try using Migration Assistant when booting from the internal drive, I get a message that the external drive is a newer OS (I forget the exact wording).


I have just loaded Monterey on the internal drive and done all Monterey updates.



Jun 22, 2023 11:10 AM in response to ku4hx

Thanks.

I wanted to re-install the MacOS on that external SSD and even with the bootable flash drive, it would not install.


It was also tricky for me to make the flash drive bootable for Monterrey while booted on Ventura, which was the only drive I had available with a MacOS on it.


I don't like to rely on TimeMachine to restore everything. Wiping my main hard drive, the external SSD, relying on TimeMachine to save everything left me uncomfortable. So I tried it first on the internal fusion drive. It worked fine and everything restored. With that test passed, trying it on the external SSD also went smoothly.

Reinstall Monterey - Can't Do It - Says Cannot Be Downgraded

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