Unable to reinstall operating system

[Hickeja]

Hi All

I am trying to fix issues with my father in laws iMac. He purchased this back in 2014.

After a storm the iMac wasn’t able to load past the Apple loading logo and would shut off. Luckily he didn’t have any data that wasn’t in his emails so I got into the Mac utility and formatted his hardrive and attempted to reinstall a new version of Mac OS. The version is was trying to install high Sierra. It had strong and stable wifi at the time of trying to reinstall.

I also noticed in the utility that the hardrive was no longer appearing, just the operating system drive.

I do apologise I am a Mac novice. I have attached some screen shots of the error message when trying to reinstall the OS and the current hardrive layout.

The iMac appears to be getting power I am just not sure if the storm is related or not and whether it’s a software or hardware issue.

Any help would be much appreciated.

 

[Bigwaff]

In Disk Utility, top left select View > Show All Devices. Post screenshot.

 

[Bigwaff]

Your HIgh Sierra fix

 

[Fishrrman]

OP:

Try Apple's "INTERNET" recovery.
It's not the same as "regular" recovery.

WARNING: going further will erase the entire drive. All personal data will be lost.
Just be aware of that.

Do this:
Power down, all the way off (pull out the plug if you have to).

I recommend that you do this using an ethernet connection.
Use wifi if you must, but ethernet will be better.

Hold down this three-key combination:
Command-Option-R
DO NOT LET GO!

While still holding those keys, press and RELEASE the power on button.

KEEP HOLDING THOSE KEYS DOWN!

You can let go when:
- if you're connected via ethernet, you see the spinning globe
or
- if you're connected via wifi, you're asked for the wifi password.

The internet utilities take a while to load, so be patient.

When the utilities are loaded, open disk utility.

IMPORTANT: check the menu bar. Is there a "view" menu?
If there is, you MUST go to it and select "show all devices".

Now, look at the list on the left.
The topmost item should be the internal drive.
We need to erase it.
So... click on it to select it, then click the erase button.

Erase to APFS, GUID partition format.
When done, quit disk utility and open the OS installer.

I believe you're going to be offered "Big Sur" as the OS (last OS that Apple supported on the 2014 iMac).
Accept it. A Mac that boots to any version of the OS is better than one that won't boot at all.

Start clicking through.
The Mac will reboot one or more times, and the screen will go dark for a minute or more with no other indication of activity.
Be patient.
When done, you should see the initial setup screen (choose your language).
Start clicking through.

You said your father didn't have a backup, is that right?
If that's the case, you'll need to create a new account for him.
He can use the same username and password, but he'll have to re-create his mail account (again, username and password with the email provider as he used before).

If you have access to a printer as you read this, PRINT OUT this reply and keep it with you.

Good luck.