How to repair Mactintosh HDD
I have a MacBook Pro 2016 15" with 256GB running macOS High Sierra. When I got the MacBook used, I was able to log in. The MacBook did not have an iCloud account linked so I linked mine up and enabled Find my Mac.
I tried to do a fresh install of macOS Sierra which cleaned out the hard drive but it says "An error occurred while preparing the installation. Try running this application again".
Disk Utility returns a code 8 for a corrupted system. Is this because I did not turn off the Find my Mac?
If your goal is to install macOS Sierra, then your best bet is to boot into macOS Recovery using the ShiftOption⌘R keyboard shortcut. That's because your model MBP originally shipped with macOS Sierra and this keyboard shortcut is designed to install the version of macOS that originally shipped with your Mac.*
To do this:
- Fully shut down your MBP
- Power up your MBP again but immediately press and hold the ShiftOption⌘R
- Keep the keys down until you see either an Apple logo or spinning globe appear on screen (Note: If you have a firmware password set on your system, then let go of the keys when the password prompt appears)
- Once the Utilities window appears you'll be in macOS Recovery Mode
Now choose to reinstall macOS and follow the prompts.
IMPORTANT - If you already have data stored on your internal drive you should do a backup first!
* For users of older Mac models this option will install the closest version of macOS still available to the original that shipped with it.