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User profile for user: fearless1225
fearless1225 Author
User level: Level 1
8 points

iMac only has OS X base system, need help badly

Hello,


I tried installing Big Sur a couple days ago and it’s been a disaster ever since.


the update was stuck and I tried option command R and other things I’ve read in forums to fix it and I’m at the point where my iMac won’t listen to any commands and takes me straight to macOS utilities upon restart.


I only have OS X Base system and I cannot erase, restore or mount. I tried to install macOS Sierra and it says I have no permission. I do have another APPLE HDD media drive right above the OS X base system and I also cannot erase, restore or mount. I tried to partition the OS X base system and the apply button never goes blue for me to actually initiate it. Really need help here. I have no time machine backup at all.

Posted on Feb 24, 2021 10:49 AM

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Question marked as Top-ranking reply
User profile for user: Jack-19
Jack-19
User level: Level 8
46,020 points

Posted on Feb 24, 2021 12:15 PM

Hi fearless1225,


Let's try these steps. Please note this will erase all data!


  1. Shut down the iMac. (if on)
  2. Turn on the iMac, 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. This will either be "APPLE SSD...", "APPLE HDD...", or "Fusion Drive".
  7. Click Erase, and input the following exactly: (If you cannot select erase on the main hard drive, erase the "Container".)
  8. Name: Macintosh HD
  9. Format: APFS (if APFS is not shown, choose Mac OS Extended Journaled)
  10. Scheme: GUID Partition Map (if shown)
  11. Click Erase
  12. Quit Disk Utility
  13. Go to the reinstall macOS app.
  14. Follow the prompts, and install on Macintosh HD.
  15. See if it installs correctly.


Cheers,


Jack

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Question marked as Top-ranking reply
User profile for user: Jack-19
Jack-19
User level: Level 8
46,020 points

Feb 24, 2021 12:15 PM in response to fearless1225

Hi fearless1225,


Let's try these steps. Please note this will erase all data!


  1. Shut down the iMac. (if on)
  2. Turn on the iMac, 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. This will either be "APPLE SSD...", "APPLE HDD...", or "Fusion Drive".
  7. Click Erase, and input the following exactly: (If you cannot select erase on the main hard drive, erase the "Container".)
  8. Name: Macintosh HD
  9. Format: APFS (if APFS is not shown, choose Mac OS Extended Journaled)
  10. Scheme: GUID Partition Map (if shown)
  11. Click Erase
  12. Quit Disk Utility
  13. Go to the reinstall macOS app.
  14. Follow the prompts, and install on Macintosh HD.
  15. See if it installs correctly.


Cheers,


Jack

Reply

iMac only has OS X base system, need help badly

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