preparing to sell MAC27 ... lost my OS disk

[albireo13]

I'm prepping my older MAC27 to sell and will be scrubbing and reformatting the drive.
I will need to re-install a fresh copy of the OS afterwards but, I lost my OS discs.

What's the best way proceed?
Can I download it somehow after scrubbing the disk?

Rob

 

[Slydude]

What OS version are you trying to reinstall?

 

[albireo13]

It is a late 2009 Mac27.
12GB RAM
1TB HDD

It is currently running Sierra V10.12.6
I believe this is the latest version that will support this machine.
Anything earlier would be fine as well.
I will sell it soon and the new user can upgrade the OS if he wishes.

 

[pigoo3]

Any OS you're going to want to install to sell this computer with is downloadable...no OS disks needed.

- Nick

p.s. If this is definitely a Late 2009 27" iMac...it can run High Sierra.

 

[ferrarr]

Start here, https://support.apple.com/en-us/HT201065.

 

[albireo13]

Won't it brain-dead after I reformat the HD, getting in the way of web access?

 

[ferrarr]

Only if you wiper the drive. But, you could create a bootable USB installer, https://support.apple.com/en-us/HT201372, and use that to install whatever macOS version you out on it. This way, when you boot from the USB, you can use Disk Utility to erase the internal drive, and then set it up as a brand new fresh clean macOS install.

 

[pigoo3]

Won't it brain-dead after I reformat the HD, getting in the way of web access?

If this computer was or is running any sort of more modern version of the macOS...then the HD has a Recovery Partition on the drive...which would not be erased with a regular "erase the HD action.

- Nick

 

[albireo13]

so, the recovery partition is preserved during a HD reformat??

 

[ferrarr]

so, the recovery partition is preserved during a HD reformat??

Yes, when accessing Disk Utility from the recovery partition.

 

[pigoo3]

so, the recovery partition is preserved during a HD reformat??

Exactly as member ferrarr mentioned. If you access Disk Utility via the Recovery Partition...and select "Erase Disk"...only the main partition of the HD is erased. The Recovery Partition is untouched...and the Recovery Partition only contains generic-stock Apple stuff (nothing personal is stored there)....thus the Recovery Partition itself does not need to be erased.

- Nick

 

[albireo13]

That worked great! Thanks a bunch.
The only glitch was during re-install my wireless keyboard was not recognized so I had to run out to the store and buy a cheap USB keyboard to complete the OS restore.
Now running Sierra and looking good.
: )

 

[Slydude]

It's always good to have a wired keyboard on hand for just this situation Even the Apple wireless keyboard does not always work when you try to use the Option key to select the boot drive.

 

[pigoo3]

That worked great! Thanks a bunch.

Now running Sierra and looking good.

Excellent & congrats!

- Nick