Urgent Help: Did I Just Brick my iMac? (Recovery Mode OS Install Attempt)

[Tricone]

I am trying to return my Late-2013 iMac 27" (Mac OS Catalina 10.15.6) to factory and have come to the stage where I boot into Recovery Mode in an attempt to install a fresh copy of Catalina. I have a 3TB Fusion Drive.

I first tried installing a copy of the OS in Recovery Mode, but got the error "The target volume is part of incomplete system and can not be installed to."

In disk utility, there are two entries: (1) Mac HD and (2) OS X Base System. Running First Aid multiple times on "Mac HD" spits out "too many warning generating, suppressing further warnings", but the process does continue to completion. Attempting to Erase "Mac HD" in Disk Utility basically times out . . . after an hour, there is no progress shown in the progress bar. When I attempt to install the OS, I cannot get past the "Continue" screen. When I attempt to restore from an external drive containing High Sierra, I receive an error message that "This operation couldn't be completed (OSStatus error 49182). I did attempt to use Terminal in Recovery Mode, and when I ran the command "diskutil list", there were 23 disks listed. Obviously, there is some issue with my Fusion Drive, but I am at a loss as to how to proceed.

Edit: Changed High Sierra to Catalina

 

[chscag]

It sounds like your hard drive, perhaps the spinner part of the fusion drive, is defective and needs to be replaced. Since your machine is out of warranty, you might want to replace the drive yourself. My recommendation is to replace it with a SSD and get rid of the fusion drive.

You can find instructions and tools at www.ifixit.com. It's not an easy job but if you're handy with repairs, you should be able to do the repair yourself.

 

[Tricone]

It sounds like your hard drive, perhaps the spinner part of the fusion drive, is defective and needs to be replaced. Since your machine is out of warranty, you might want to replace the drive yourself. My recommendation is to replace it with a SSD and get rid of the fusion drive.

You can find instructions and tools at www.ifixit.com. It's not an easy job but if you're handy with repairs, you should be able to do the repair yourself.

The drive was functioning perfectly minutes before. In the process of getting the iMac ready to sell, was able to boot into the OS normally, and perform the various recommended checklist items when selling, e.g. unchecking Find My, signing out of iCloud, deauthorizing iTunes, unpairing bluetooth devices, etc, as suggested by an online guide (iMore). I then rebooted into Recovery Mode, and proceeded into Disk Utility, and under advisement, first deleted the data disk under the startup disk. My inability to erase anything else, or install a new OS from Recovery Mode began then. In fact, when I ran First Aid on the Fusion Drive itself, the operation completed successfully, but found a large number of "MT mapping errors". Not sure what that means. I believe the drive itself is sound. Something else is going on . . .

 

[Taz Mangus]

I would suggest booting into Recovery Mode and run first aid on the drive. Also, download the High Sierra and create and bootable USB of the installer. Boot to the installer and use it to install on the drive.

‎macOS High Sierra

‎New technologies at the heart of the system make your Mac more reliable, capable, and responsive — and lay the foundation for future innovations. macOS High Sierra also refines the features and apps you use every day. It’s macOS at its highest level yet. Easily organize, edit and view your...

apps.apple.com

Create a bootable installer for macOS - Apple Support

You can use a USB flash drive or other secondary volume as a startup disk from which to install the Mac operating system. These steps are primarily for system administrators and other experienced users who are familiar with entering commands in Terminal.

support.apple.com

 

[Tricone]

I would suggest booting into Recovery Mode and run first aid on the drive. Also, download the High Sierra and create and bootable USB of the installer. Boot to the installer and use it to install on the drive.

‎macOS High Sierra

‎New technologies at the heart of the system make your Mac more reliable, capable, and responsive — and lay the foundation for future innovations. macOS High Sierra also refines the features and apps you use every day. It’s macOS at its highest level yet. Easily organize, edit and view your...

apps.apple.com

Create a bootable installer for macOS - Apple Support

You can use a USB flash drive or other secondary volume as a startup disk from which to install the Mac operating system. These steps are primarily for system administrators and other experienced users who are familiar with entering commands in Terminal.

support.apple.com

I did boot into Recovery Mode and ran First Aid, to no avail. I also have a High Sierra bootable external USB drive, which I even tried to restore from. It could not be installed on the Fusion Drive, spitting out an error "The target volume is part of incomplete system and can not be installed to."

 

[Taz Mangus]

When you erased the drive did you first do in Disk Utility->View->Show All Devices and erase the physical device listed at the top?

You will need to use the bootable USB of High Sierra to do the full erase.

 

[Tricone]

When you erased the drive did you first do in Disk Utility->View->Show All Devices and erase the physical device listed at the top?

I basically followed the recommendations given here:

https://www.imore.com/how-to-prepare-mac-for-sale

The part in question, Step 4, stated to "Show all Devices", as I did, but then select the "data disk" under the startup disk, and then delete this volume, which I did. It was the only data disc that I saw.

 

[Taz Mangus]

Those instructions are for Catalina reinstall. You are reinstalling High Sierra. You need to do the erase on the physical drive itself and erase it as Mac OS Extended.

 

[Tricone]

Those instructions are for Catalina reinstall. You are reinstalling High Sierra. You need to do the erase on the physical drive itself and erase it as Mac OS Extended.

Actually, I was reinstalling Catalina. Catalina was the OS on the iMac prior to getting it ready for selling. Attempting to reinstall Catalina via Recovery Mode failed. Any attempt to repair or erase the Fusion Drive failed. Incidentally, when I tried to erase the physical drive, only APFS was an option.

Only after my attempts failed did I get the "smart/dumb" idea to try and restore from my High Sierra external drive.

Oh, and when I ran Terminal in Recovery Mode -> diskutil list, it listed 23 disks!

 

[Taz Mangus]

Actually, I was reinstalling Catalina. Catalina was the OS on the iMac prior to getting it ready for selling. Attempting to reinstall Catalina via Recovery Mode failed. Any attempt to repair or erase the Fusion Drive failed. Incidentally, when I tried to erase the physical drive, only APFS was an option.

Only after my attempts failed did I get the "smart/dumb" idea to try and restore from my High Sierra external drive.

Oh, and when I ran Terminal in Recovery Mode -> diskutil list, it listed 23 disks!

Your first post:

I am trying to return my Late-2013 iMac 27" to factory and have come to the stage where I boot into Recovery Mode in an attempt to install a fresh copy of High Sierra. I have a 3TB Fusion Drive.

 

[Tricone]

Thanks for pointing that out!

It seems I obviously messed up my Fusion Drive. After all this futzing, I decided minutes ago to restart into Recovery Mode and restore from a Time Machine backup. Low and behold, it seems to be restoring okay. Crossing my fingers. However, this will leave me at square one, as I still need to somehow get it to factory.

 

[chrfr]

Oh, and when I ran Terminal in Recovery Mode -> diskutil list, it listed 23 disks!

That’s normal when booted to recovery mode.