How can I reset my MacBook Air with Mac OS Sierra? I tried going to disc utility and I am not able to erase my Macintosh HD. It says this operation cannot be performed because you cannot unmount the volume you are booted from. Please help me erase and reset.
Correct, you cannot erase the drive you're booted from...
Start up from macOS Recovery
Option-⌘-R
Upgrade to the latest macOS compatible with your Mac.
In Disk Utility>View, select Show all Devices, highlight the top left entry.
APFS won't work for Sierra or earlier, Sierra or earlier needs MacOS Extended Journaled. High Sierra won't work for APFS on earlier Macs.
What has often worked for others is to use this Restore Method instead of CMD+r keys...
Option-⌘-R
Upgrade to the latest macOS compatible with your Mac.
Messed up Factory Reset on MacBook Pro Mi… - Apple Community
https://discussions.apple.com/thread/254793247?answerId=258936149022#258936149022
Clean Install of High Sierra: Multiple Fa… - Apple Community
An Error Occurred While Preparing The Ins… - Apple Community
Thanks to Clo3y…
https://apple.stackexchange.com/questions/309399/how-can-i-download-an-older-version-of-os-x-macos
Correct, you cannot erase the drive you're booted from...
Start up from macOS Recovery
Option-⌘-R
Upgrade to the latest macOS compatible with your Mac.
In Disk Utility>View, select Show all Devices, highlight the top left entry.
APFS won't work for Sierra or earlier, Sierra or earlier needs MacOS Extended Journaled. High Sierra won't work for APFS on earlier Macs.
What has often worked for others is to use this Restore Method instead of CMD+r keys...
Option-⌘-R
Upgrade to the latest macOS compatible with your Mac.
Messed up Factory Reset on MacBook Pro Mi… - Apple Community
https://discussions.apple.com/thread/254793247?answerId=258936149022#258936149022
Clean Install of High Sierra: Multiple Fa… - Apple Community
An Error Occurred While Preparing The Ins… - Apple Community
Thanks to Clo3y…
https://apple.stackexchange.com/questions/309399/how-can-i-download-an-older-version-of-os-x-macos
Reset MacBook MacOS sierra
