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I did an erase on my internal now it won’t let me reinstall iOS

How to get operating system back on my iMac?

iMac Line (2012 and Later)

Posted on Jul 23, 2021 6:15 AM

Reply
Question marked as Top-ranking reply

Posted on Jul 23, 2021 6:16 AM

Welcome to Apple Support Communities.


Please follow these steps:


  1. Shut down the Mac.
  2. Turn on the Mac, and immediately press and hold Option + Command + R until you see a spinning globe.
  3. Once you are in macOS Recovery, verify you are connected to WiFi in the top right corner. If possible, connect directly to the internet with Ethernet. 
  4. Go to Disk Utility.
  5. Select "View" in the toolbar > "Show All Devices".
  6. Select your main hard drive or SSD. This will be the top, non indented hard drive. 
  7. Click Erase, and input the following exactly: (If you cannot select erase on the main hard drive, erase the "Container" or “Macintosh HD”.)
  8. Name: Macintosh HD
  9. Format: APFS
  10. Scheme: GUID Partition Map (if shown)
  11. Click Erase. If “Erase Volume Group” is shown, use that instead. 
  12. Quit Disk Utility
  13. Go to the reinstall macOS app.
  14. Follow the prompts, and install on Macintosh HD.


Jack

3 replies
Question marked as Top-ranking reply

Jul 23, 2021 6:16 AM in response to Mpaint1

Welcome to Apple Support Communities.


Please follow these steps:


  1. Shut down the Mac.
  2. Turn on the Mac, and immediately press and hold Option + Command + R until you see a spinning globe.
  3. Once you are in macOS Recovery, verify you are connected to WiFi in the top right corner. If possible, connect directly to the internet with Ethernet. 
  4. Go to Disk Utility.
  5. Select "View" in the toolbar > "Show All Devices".
  6. Select your main hard drive or SSD. This will be the top, non indented hard drive. 
  7. Click Erase, and input the following exactly: (If you cannot select erase on the main hard drive, erase the "Container" or “Macintosh HD”.)
  8. Name: Macintosh HD
  9. Format: APFS
  10. Scheme: GUID Partition Map (if shown)
  11. Click Erase. If “Erase Volume Group” is shown, use that instead. 
  12. Quit Disk Utility
  13. Go to the reinstall macOS app.
  14. Follow the prompts, and install on Macintosh HD.


Jack

Jul 23, 2021 6:37 AM in response to Mpaint1

You need to make sure you erase the Volume Group for Macintosh HD. Boot into Recovery OS then open Disk Utility and change the View to "Show All Devices". Click on the Container that holds Macintosh HD and Erase that Container. This will remove all volumes and format a new Macintosh HD volume. Last, try your reinstall again.

I did an erase on my internal now it won’t let me reinstall iOS

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