macOS Sequoia (15.0): How to Fix APFS Disk Formatting Issues

Fixing APFS Formatting Errors in macOS Sequoia

Formatting drives to APFS in the macOS Sequoia (15.0) Disk Utility can sometimes result in errors, particularly on NVMe drives or when reusing drives that previously contained Windows partitions or older macOS installations. Errors like "Erase process has failed" or unmountable APFS containers are common.

Why Does This Happen?

macOS Sequoia introduces stricter disk health and partition map validations. If a drive contains residual EFI partitions, hidden Microsoft Reserved partitions, or an old CoreStorage volume, Disk Utility's GUI may fail to wipe it cleanly. Additionally, some third-party NVMe SSDs (like certain Samsung or Kingston models) may require specific OpenCore quirks to format correctly.

Step-by-Step Fix via Terminal

The most reliable way to force-format a stubborn drive is by bypassing the Disk Utility GUI and using the Terminal from the macOS Recovery or Installer environment.

1. Boot into the macOS Sequoia Installer USB.
2. Instead of opening Disk Utility, go to the top menu bar, click Utilities, and select Terminal.
3. Type diskutil list and press Enter. This will show a list of all connected drives. Identify the identifier of the drive you want to format (e.g., disk0, disk1). Be extremely careful to select the correct drive!
4. Execute the following command to completely wipe the partition map and format the drive as APFS:
   diskutil eraseDisk APFS "Macintosh HD" GPT diskX
   (Replace diskX with your actual drive identifier, e.g., disk0).
5. Wait for the process to complete. You should see a message saying "Finished erase on diskX".
6. Close Terminal, open Disk Utility, and verify that the drive is now correctly showing as "Macintosh HD" formatted in APFS.

NVMe Compatibility Check (OpenCore)

If the terminal command hangs or fails, your NVMe drive might have compatibility issues with macOS Sequoia. Ensure you have the NVMeFix.kext installed in your OpenCore configuration. If you are using a Samsung PM981 or 970 EVO Plus with old firmware, you may experience kernel panics during formatting. Always update your NVMe firmware via Windows or a Linux Live USB before attempting to install macOS.