MacOS could not be installed on your computer

[Mizu7]

Hello,

I have a problem installing MacOS to iMac. I wanted a new (clear) macos on it, so I deleted Macintosh HD, where macos was installed via Command+R recovery mode using disk utility. Then in recovery mode I clicked on install a new copy of MacOS, it started downloading but in the half of installation, it restarts and gives me error "MacOS could not be installed on your computer", then it says something about problem with copying. I also called apple support, but with no luck. Could you please help me? This is what I´ve done:

Erased Macintosh HD to MacOS Extended (Journaled) - but still, the same error.
Tried to power on computer with command, option, P, R. Still the same.
Tried internet recovery and installing again. The same.
Tried to create a bootable macos installer on USB via my Macbook. Still the same.

Do you have any suggestions please? Thank you.

 

[294307]

Try holding down Option-Command-R when starting up your Mac to reinstall the latest version of macOS that's compatible with your Mac. If that doesn't work, you'll need to try reinstalling the version of macOS that came with your Mac by holding down Shift-Option-Command-R.

 

[Mizu7]

Tried this also Still in the middle of it, it restarts and gives me error. There must be something behind it, what I am doing wrong and don´t know what it is. Is it okay to have HDD formated to MacOS Extended (Journaled)?

 

[BrianBaughn]

You may have discovered that your hard drive has some bad sectors on it and the installation fails when it tries to write to one or more of them.

Alternately, it could be that your hard drive cable is dodgy and that's throwing errors.

Successfully installing to an external drive would be a second indicator of one of those issues with your internals.

 

[Mizu7]

I´ll try that with external drive. That´s a good point. Thanks.
But I don´t think there is a problem with HDD, because I used diagnostic tool (starting with D button) and there was no error. Also, it was working 100% right before I deleted it.

 

[BrianBaughn]

The Diagnostic Tool does what it does but there's no way it could check every block on a hard disk in the time that it runs so one would have to assume it is not checking blocks.

I recently had a Samsung SSD that was running fine but a block-level scan revealed bad blocks. I got a replacement via warranty.

 

[Fishrrman]

OP:
Why don't you tell us WHICH iMac you have?
And... what version of the OS you're trying to install?

MacConfucious say:
User who erases Mac without backup...
... often finds himself "backed up" against the wall...

 

[Mizu7]

Hi guys, thank you for your help! Shift - Command - Option - R finally helped.