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User profile for user: Kevin_C
Kevin_C Author
User level: Level 1
20 points

Can't reinstall Big Sur from recovery mode, won't allow me to select system disk

I am attempting to re-install Big Sur 11.3 from recovery mode on my system disk.


When selecting my internal disk when attempting to do this, I receive the following error:


The operation couldn't be completed. (com.apple.BuildInfo.preflight.error error 21.)


Have no idea what it could be, searches weren't any help.


Troubleshooting steps already tried to no avail:

  • Restarting
  • Resetting the SMC and PRAM on the Mac Mini
  • Running First Aid from Disk Utility on the target drive
  • Running First Aid on all drives connected to the system


I'm at a loss as to what to do next, or even knowing what's causing the error, let alone how to fix it. Hoping someone can help!

Mac mini 2018 or later

Posted on May 1, 2021 5:19 AM

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Question marked as Top-ranking reply
User profile for user: Jack-19
Jack-19
User level: Level 8
46,014 points

Posted on May 1, 2021 6:05 AM

Hi Kevin_C,


If you just want to Reinstall, 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.
  4. Go to the reinstall macOS app.
  5. Follow the prompts, and install on Macintosh HD.


If you just want to Reinstall and erase your Mac, 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.
  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.


Cheers,


Jack

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Question marked as Top-ranking reply
User profile for user: Jack-19
Jack-19
User level: Level 8
46,014 points

May 1, 2021 6:05 AM in response to Kevin_C

Hi Kevin_C,


If you just want to Reinstall, 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.
  4. Go to the reinstall macOS app.
  5. Follow the prompts, and install on Macintosh HD.


If you just want to Reinstall and erase your Mac, 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.
  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.


Cheers,


Jack

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Can't reinstall Big Sur from recovery mode, won't allow me to select system disk

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