User profile for user: orrpix
orrpix Author
User level: Level 1
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Upgrade from El Capitan to Monterey

I am passing my late 2015 iMac that was running Monterey to my son.

I followed Apple's procedure for handing over iMac to new owner which involved a reformat of the operating disks.

This process installed El Capitan rather the Monterey. I want Monterey to allow use of Pages, Numbers, Keynote from app store.

I have a non-standard disk configuration because I upgraded my 1 TB Fusion drive to an internal 2 TB SSD, but still have the legacy 120 GB PCI Internal Physical volume Apple SSD, which was forming part of the Apple Fusion drive.

App Store is not listing Monterey as an upgrade option.

The El Capitan installed on the 120 GB drive and I want to change the startup to the 2 TB SSD.

However, I can't see the 2 TB SSD as an option in the change startup disk app.

How do I convince the iMac to install Monterey on the 2 TB SSD?


iMac

Posted on Feb 13, 2023 1:59 AM

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User profile for user: orrpix
orrpix Author
User level: Level 1
5 points

Posted on Feb 13, 2023 3:23 PM

No, the Fusion Drive didn’t break, but the hard disk component was showing signs of wear by becoming noisy and slow. I was attracted by the challenge of getting inside the iMac via the ifixit website in order to upgrade the size and speed via a 2 TB SSD install while keeping the legacy small SSD working alongside it.


I went through the process you described in your reply but each time the install got to the last 10 minutes (after starting for an estimated 2 hours and 14 minutes, moving up to 7 hours then actually stopping after about 3 hours with a failed install message popping up. This happened three times after disk reformats and cold reboots.


interestingly, Monterey didn’t ever appear as an upgrade option so I had to search for a Monterey download myself, as it wasn’t listed in App Store for this late 2015 iMac, even though Apple support its use with this model.


After posting my first message I guessed that perhaps Apple didn’t like installing Monterey onto a third party internal SSD, so I pointed the next OS install to the little in-house SSD (120 GB) and it finally succeeded in the upgrade from El Capitan to Monterey, taking about 2 hours with a 75 MB wifi link.


So now I have the latest (and last) OS for the iMac, meaning I can now install the latest Pages, Numbers and Keynote which won’t run under El Capitan.


Thanks for your comments.

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User profile for user: orrpix
orrpix Author
User level: Level 1
5 points

Feb 13, 2023 3:23 PM in response to BDAqua

No, the Fusion Drive didn’t break, but the hard disk component was showing signs of wear by becoming noisy and slow. I was attracted by the challenge of getting inside the iMac via the ifixit website in order to upgrade the size and speed via a 2 TB SSD install while keeping the legacy small SSD working alongside it.


I went through the process you described in your reply but each time the install got to the last 10 minutes (after starting for an estimated 2 hours and 14 minutes, moving up to 7 hours then actually stopping after about 3 hours with a failed install message popping up. This happened three times after disk reformats and cold reboots.


interestingly, Monterey didn’t ever appear as an upgrade option so I had to search for a Monterey download myself, as it wasn’t listed in App Store for this late 2015 iMac, even though Apple support its use with this model.


After posting my first message I guessed that perhaps Apple didn’t like installing Monterey onto a third party internal SSD, so I pointed the next OS install to the little in-house SSD (120 GB) and it finally succeeded in the upgrade from El Capitan to Monterey, taking about 2 hours with a 75 MB wifi link.


So now I have the latest (and last) OS for the iMac, meaning I can now install the latest Pages, Numbers and Keynote which won’t run under El Capitan.


Thanks for your comments.

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User profile for user: BDAqua
BDAqua
User level: Level 10
250,253 points

Feb 13, 2023 11:54 AM in response to orrpix

Did you break the Fusion drive?


How to fix a split Fusion Drive

If your Fusion Drive appears as two drives instead of one in the Finder, it's no longer working as a Fusion Drive. Here's how to fix it.

How to fix a split Fusion Drive - Apple Support

diskutil resetapple fusion join


If your Mac has a Fusion Drive and you see a flashing question mark or alert, see the troubleshooting section of the Apple Support article About Fusion Drive, a storage option for some Mac computers.

If you continue to have problems with your disk or it can’t be repaired, it may be physically damaged and need to be replaced. For information about servicing your Mac, see Find out how to service or repair your Mac.


In Terminal…

diskutil resetFusion


https://wpbeaches.com/apple-minimum-system-requirements-for-macos-monterey-12/


To start up from macOS Recovery, turn on your Mac and immediately press and hold one of the following combinations on your keyboard. Command-R is generally recommended, especially if you never installed macOS Sierra 10.12.4 or later… How to reinstall macOS - Apple Support

Command (⌘)-R

Install the latest macOS that was installed on your Mac.


Option-⌘-R

Upgrade to the latest macOS compatible with your Mac.


Shift-Option-⌘-R

Install the macOS that came with your Mac, or the closest version still available.



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Upgrade from El Capitan to Monterey

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