What does 'Volume could not be repaired' mean?

First Aid found errors beyond its ability to fix. Try fsck from single-user mode, or back up data and reformat the drive.

Should I run First Aid on the container or volume?

For APFS, run First Aid on both. Start with the container, then check individual volumes. Container-level fixes can resolve volume issues.

Mac Disk Utility First Aid Errors — Repair & Volume Recovery

Errordisk

Overview

Fix Disk Utility First Aid errors including 'First Aid found corruption that needs to be repaired', 'could not be repaired', and volume header issues.

Key Details

First Aid checks and repairs file system errors on HFS+, APFS, and FAT volumes
Cannot repair the boot volume while macOS is running — use Recovery Mode
APFS container errors may require checking both the container and individual volumes
Common issue: 'Volume could not be repaired' means First Aid found errors it cannot fix
fsck (file system check) in single-user mode can fix errors Disk Utility cannot

Common Causes

Power loss or improper shutdown causing file system inconsistency
Bad sectors on HDD or failing flash cells on SSD
APFS snapshot corruption from interrupted Time Machine backups
Volume header or catalog file corruption
Physical disk damage that software cannot repair

Steps

1Boot to Recovery Mode (Cmd+R or hold power on M-series), open Disk Utility, run First Aid
2If First Aid fails: boot to Recovery > Terminal > diskutil repairVolume /dev/diskXsY
3For APFS: run First Aid on the container first, then individual volumes
4Try fsck in single-user mode: restart holding Cmd+S, run /sbin/fsck -fy
5If repair fails completely: back up what you can, erase the volume, and restore from backup