◆Error Codes Wiki

Mac Error 69877 APFS Disk Utility Fix

Criticalmac disk

Overview

Mac Error 69877 occurs in Disk Utility when erasing or partitioning APFS volumes. Usually a process lock issue.

Key Details

  • Error: 69877 — Could not unmount disk
  • Category: macOS Disk Error
  • Cannot erase or partition the volume
  • A process is using the disk

Common Causes

  • Spotlight is indexing the drive
  • Time Machine is using the drive
  • An application has files open on the drive
  • The startup disk cannot be erased while booted from it

Steps

  1. 1Boot into Recovery Mode (Command+R at startup)
  2. 2Use Disk Utility from Recovery to erase the drive
  3. 3Use Terminal in Recovery: diskutil eraseDisk APFS "Macintosh HD" /dev/disk0
  4. 4Close all apps using the drive before erasing

Tags

macmac-diskmac error 69877macosapple

More in Mac Disk

mac-error-69854Mac Error 69854 Partition Map Fix
Critical
mac-disk-not-ejectedMac "Disk Not Ejected Properly" Warning Fix
Informational

Frequently Asked Questions

You cannot erase the disk you booted from. Use Recovery Mode instead.