HD locked, won’t let me reinstall High Sierra. Please help

[Ahdahlyne]

Hi guys ! I’m new to this. I’m hoping I can get some help. I read a forum similar to mine & I noticed @Weaselboy is very helpful , I also tried using his steps however no luck for me. I don’t want to continue just because I don’t want to mess it up.
So here’s what happened;

My friend came over so she can buy off my iMac.

iMac 5K i5 2017
It stores 1TB & Memory of 8GB
It was running on MacOS .

She said she knew how to reset the iMac , as if it was a new one. I let her . She did the COMMAND+R .However, when she finished, it wasn’t letting her reinstall the MacOS high Sierra. It shows the disk is locked. It also shows two of them. & she told me when she went to disk utility she erased both internal disks that appear on there. If anybody can please help me, I would really appreciate it. I also included pictures on what she did & what it says when I run terminal (Based on what I read from a different forum)

I also don’t have a time machine backup.

 

[pldelisle]

Boot using Option-⌘-R. This will download Catalina 10.15.6.

diskutil eraseDisk APFS <Disk Name> /dev/<DiskNodeID>

should then do the trick.

 

[Ahdahlyne]

Boot using Option-⌘-R. This will download Catalina 10.15.6.

should then do the trick.

thank you for responding!
So I turn off computer, when I start it up. I use
Option+Command+R
From there I head to terminal & type that in correct?

 

[pldelisle]

thank you for responding!
So I turn off computer, when I start it up. I use
Option+Command+R
From there I head to terminal & type that in correct?

Yep exactly.

 

[Ahdahlyne]

Yep exactly.

Okay. So far it’s still loading. It shows this (Picture attached) & I’m hoping it can be done before I head to work , otherwise I will have to continue when I’m back from work. I’m out at 2am Central time.

 

[Brian33]

If you have trouble erasing the internal storage device with the command line, you should be able to do it from Disk Utility (either in High Sierra or in Catalina) -- but you must go to Disk Utility-->View menu and select "Show All Devices". Then DU will still show the "Macintosh HD" and "Macintosh HD - Data" volumes, and it will also show a "higher level" label that represents the actual physical storage device. It might be labeled "Apple SSD..." or something like that.

You want to select the top-most device and Erase that.

 

[Ahdahlyne]

Yep exactly.

I just got back from work , I left around 5pm. & the screen is still the same .

 

[nambuccaheadsau]

Have a read of this you do not need to go into Terminal.

How to start up from macOS Recovery – Apple Support (AU)

macOS Recovery is the built-in recovery system of your Mac, with utilities to reinstall macOS, repair or erase your startup disk, restore from a Time Machine backup and more.

support.apple.com

 

[Ahdahlyne]

If you have trouble erasing the internal storage device with the command line, you should be able to do it from Disk Utility (either in High Sierra or in Catalina) -- but you must go to Disk Utility-->View menu and select "Show All Devices". Then DU will still show the "Macintosh HD" and "Macintosh HD - Data" volumes, and it will also show a "higher level" label that represents the actual physical storage device. It might be labeled "Apple SSD..." or something like that.

You want to select the top-most device and Erase that.

I found what you were saying, so after I erase. What’s the next step? Do I head over to re-install?

 

[pldelisle]

Is the terminal command worked?

 

[Brian33]

Your Disk Utility screenshot shows two physical devices, so it looks like you have a Mac that came with a "Fusion drive". Is that right?

From what I see it looks like your previous installation was on the APPLE HDD only? You would get best performance if you restored the Fusion drive setup and then installed macOS on that. Unfortunately, I don't recall how to "fuse" the two together again (I don't have a fusion drive).

I believe you could erase and install macOS on just the APPLE HDD (the spinning drive), but performance would be poor without the Fusion drive set up...

 

[Brian33]

This looks like what you need:

https://support.apple.com/en-us/HT207584

If you boot the Catalina installer (using Internet Recovery), it looks as simple as "diskutil resetFusion" command in Terminal.app. If you boot to regular recovery (which installs High Sierra), it's a bit more complicated.