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Unable to Access External Drives and Disk Utility Shows Loading on Mac

Since I updated to macOS Sonoma, I've been experiencing issues with my external drives (exFAT). I can't access them, nor can I access Disk Utility (which continuously displays the Loading disks). Only when I use the Disk Arbitrator app to prevent the drives from mounting, it allows me to run Disk Utility and use First Aid to enable access to the external drive. However, the folder icon images are missing, and in the Sharing & Permissions info, it reads "You have custom access." Is anyone else experiencing similar problems, or does anyone know how to resolve this? Thank you very much.

Best Answered by

iBoysoft author Sherry Song

Sherry Song

Answered on Tuesday, January 27, 2026

Hello, according to your case, you can try these fixes below:

  1. Restart Mac.
  2. Adjust Finder settings.
  3. Reset PARM and NVRAM.
  4. Reset SMC.
  5. Delete the preferences files for Disk Utility.
  6. Unstick DFisk Utility with Terminal.
  7. Restart Mac in Safe Mode.
  8. Repair the hard dive in Recovery Mode.

If all of them fail, maybe you have to reformat your drive or reinstall your macOS. Be careful to do backups of your external drive because formatting or reinstalling will cause data loss.

Also read: Disk Utility Stuck on Loading Disks on Mac

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