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Problem installing Big Sur on I Mac

Spent all day unsuccessfully installing Big Sur. I disconnected all drives. Cleaned the main drive but it stops with the message below. How do I overcome or fix this?

Posted on Mar 10, 2021 9:22 AM

Reply
Question marked as Top-ranking reply

Posted on Mar 11, 2021 2:15 PM

Hey Yugan21,


Thanks for visiting Apple Support Communities. We understand that you're having an issue upgrading to macOS Big Sur due to an alert with the storage verification. When you say you "cleaned the drive", do you mean you reclaimed disk space or something else? If you haven't already, start to macOS Recovery and use Disk Utility to repair the hard drive. Just in case, here's how: How to repair a Mac disk with Disk Utility


If that doesn't help, let us know more details:


  • Which macOS version is currently installed? To find out select the Apple menu > About This Mac > Overview.
  • What format is the hard drive in currently? Disk Utility can show you.


The more details you can provide the better.


Take care.

3 replies
Question marked as Top-ranking reply

Mar 11, 2021 2:15 PM in response to Yugan21

Hey Yugan21,


Thanks for visiting Apple Support Communities. We understand that you're having an issue upgrading to macOS Big Sur due to an alert with the storage verification. When you say you "cleaned the drive", do you mean you reclaimed disk space or something else? If you haven't already, start to macOS Recovery and use Disk Utility to repair the hard drive. Just in case, here's how: How to repair a Mac disk with Disk Utility


If that doesn't help, let us know more details:


  • Which macOS version is currently installed? To find out select the Apple menu > About This Mac > Overview.
  • What format is the hard drive in currently? Disk Utility can show you.


The more details you can provide the better.


Take care.

Mar 11, 2021 8:54 PM in response to TammyW_03

Thanks for the reply. Here is the information:

Current is version: Mojave 10.14.6

Volume type :         APFS Container

BSD device node :      disk2

Connection :         SATA

Device tree path :      IODeviceTree:/PCI0@0/SATA@17/PRT0@0/PMP@0

Writable :         No

Is case-sensitive :       No

Volume capacity :      3,121,401,434,112

Available space (Purgeable + Free) : 363,098,238,976

Purgeable space :      0

Free space :         363,098,238,976

Used space :         2,758,303,195,136

Owners enabled :      No

Is encrypted :         No

Can be verified :       Yes

Can be repaired :      Yes

Bootable :        No

Journaled :        No

Disk number :        2

Media name :        AppleAPFSMedia

Media type :        Generic

Ejectable :         No

Solid state :         No

SMART status :      Not Supported


When I first ran First Aid it did not complete (no progress bar / “Done” greyed out). Checking the detail window I saw lots of errors, unfortunately I did not record them. The latest First Aid run did not complete, with the spinning disc running continuous. Had to  hit “escape” to stop it. My guess is it must be a hard drive fault. I have ordered a 4tb SSD for replacement next week and hope this solves the problem.


I also tried to install Big Sur on an external USB flash drive, although the installer on the USB seemed to have gone to plan, but when I tried to select it as a “start up disk”, in system preferences, it did not show up as an alternative in the window to start my Mac from. So I am stuck with my old System, meaning I can’t load or run Octane Render.


Thanks for you kind help.

Problem installing Big Sur on I Mac

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