I Think I Just Broke My New iMac

[Johnny Mickelman]

Anyways I'm trying to detail my attempts at getting this iMac back or at least saving my files..

I've had to give up today. I couldn't get target disk mode to work - just wouldn't see the drive from the host.

Want to try and start it up from a bootable plug-in drive but I'm stuck right now with a too-new computer and too-new stuff at Apple store and all of my drives and solutions are too old to plug into the 2013 iMac

My next attempt is going to be to install a bootable Catalina onto an old school USB drive I have and see if I can gain access like that.

 

[Johnny Mickelman]

Ok, so I managed to make a bootable Catalina on an external drive after following these instructions (https://support.apple.com/en-us/HT201372) and using Terminal

But when I plugged it into the iMac and started while holding Alt it didn't do what the rest of that article said would happen - instead I got a slightly more modern-looking version of the 'choose network' dropdown for selecting Wi-Fi but above that a new option - 'install Catalina' - which wasn't what I was expecting but I clicked thru that because there was no other option - now I'm watching the normal Apple Apple progress bar on black screen - then it opened up a recovery mode but now in the Catalina OS

Once again I had the options of running disk utility or reinstalling the OS - instead I went to startup disk and this time the drive did show up and I chose to reboot from that

Then another black screen and progress bar.. which put me back into recovery mode again.

this time I ran Disk Utility on everything I could see - using the View All Devices drop down to do all the drives.

Then I just thought I'd hit restart to see what different that made.

It did a whole startup process with black screen and progress bar which took a bit longer than usual but when it was done it went thru and did it again much faster then it went to a lighter grey screen and back into recovery mode

Once again I selected the bootable drive as startup disk and restarted (I'm doing this because the only other option I have is to reinstall the OS and I thought I was doing that from this bootable drive - maybe I've gotten that wrong but I'm going to do this one more time to see if it's made any changes)

One thing that's really worrying is that the name for the hard drive in Disk Utility is just Untitled and says that there is nothing on it - I'm going to ignore this right now.

So I bit the bullet and clicked thru reinstall OS and luckily yes it's Catalina, I clicked thru and there were no more options so I just got it underway, I should know in about 6mins what's left of my computer..

 

[Johnny Mickelman]

Ok so after multiple start up screens I finally got to reinstall Catalina and it looks like a clean install but everything is gone, absolutely everything - it's like I plugged it in for the first time - probably lost about 400gb of stuff that was nowhere else..

Any ideas if anything is recoverable I'd love to hear from you.

 

[iStorm]

Ok so after multiple start up screens I finally got to reinstall Catalina and it looks like a clean install but everything is gone, absolutely everything - it's like I plugged it in for the first time - probably lost about 400gb of stuff that was nowhere else..

Any ideas if anything is recoverable I'd love to hear from you.

In your post #114, a couple screenshots show Capacity: 1.12 TB, Available: 1.11 TB, Used: 8.51 GB. It’s likely the ‘fix’ repartitioned the drive since it didn’t know how to read the new APFS file system. This basically wipes out the table or index that keeps track of your partitions/volumes and where your files are on the disk.

Hate to say it, but your data is gone. If it really needs to be recovered, you need to shutdown the Mac ASAP to prevent more bits from being overwritten, and take it into a data recovery service to see if anything is salvageable.

 

[DeltaMac]

Not wanting to throw insult after injury.... but -- you were doing OK, successfully making, then booting to the Catalina installer.
As with any OS X/macOS installer since Lion, if you boot to the bootable installer, it will look just like a recovery system.
It is not a particularly useful system, as there is no graphical user interface (GUI) to copy files, or even just to browse through other drives. All you get is a couple of utilities, usually Disk Utility and Terminal, sometimes Safari or the System Information utility, and the choice to reinstall OS X/macOS.
And, you need a destination, some other volume that has been prepared to accept the system install.
Your drive was erased (the Mountain Lion recovery probably did that when it tried to "fix" your drive. And, without naming the new drive, it used the default name "Untitled". The system does not automatically name the factory "Macintosh HD", that is a choice when the drive is erased.
So, you then installed the Catalina system on the already "fixed" drive. The "fix" returned the format for the drive to Mac OS Extended (Mountain Lion doesn't know what to do with APFS), then running the Catalina installer on that same "fixed" drive, then made it worse by changing the format again to APFS. Unfortunately, that takes you even further down the path of losing any possibility of recovering any files.

If you want to try to get your files, stop where you are, and call these guys - https://drivesaversdatarecovery.com
They will give you some choices, and let you know about the charge for that service

 

[Johnny Mickelman]

In your post #114, a couple screenshots show Capacity: 1.12 TB, Available: 1.11 TB, Used: 8.51 GB. It’s likely the ‘fix’ repartitioned the drive since it didn’t know how to read the new APFS file system. This basically wipes out the table or index that keeps track of your partitions/volumes and where your files are on the disk.

Hate to say it, but your data is gone. If it really needs to be recovered, you need to shutdown the Mac ASAP to prevent more bits from being overwritten, and take it into a data recovery service to see if anything is salvageable.

Yeah, that's where it all went wrong, after that point it displayed the folder with question mark (so much for the 'fix')

I understand that I don't have many options any more but I have been in this situation in the past and recovered stuff. I used to have TechTool and something else I can't remember the name of and managed to retrieve files by repairing the 'catalog B-tree' and all that - any way of doing that in modern times or am I hopelessly out of date?

I was just under the impression that tables and indexes can be recreated and nothing is really 'deleted' until it is overwritten or zeroed-out?

Data Recovery Services.. I know but I don't have money for that

If you're thinking I'm an idiot and should've backed stuff up well, this was my back-up - everything else was older or fuller than this Mac which was 'new' to me a year ago.