USB wont mount, how can I recover data?

I have a 1TB USB that wont mount. Disk utility calls it disk2s2 and First Aid isnt available. After awhile I get an error message saying the disk cant be unlocked, using the name I gave it. When I remove it, it says internal state error occurred. System Info shows 209mb free and a Disk Drill scan I did awhile back showed the files were still on there, even though Disk Drill shows the original disk name. Is there any way I can access and transfer my files without paying for disk drill?

Earlier Mac models

Posted on Jan 8, 2026 6:38 AM

Reply
Question marked as Top-ranking reply

Posted on Jan 9, 2026 10:03 AM

Yes — you likely can recover your files without paying for Disk Drill, and based on what you described, the data is probably still there. The “can’t be unlocked” message strongly suggests the drive is encrypted (APFS or HFS+), and macOS is failing during the unlock/mount step rather than the data being gone.


So why this is happening? From your symptoms:

  • “Can’t be unlocked”
  • “Internal state error”
  • Disk Drill sees files
  • System Info shows wrong free space


This points to: Corrupted APFS encryption metadata, not dead storage. The drive is readable at the block level — that’s why recovery tools can see files.


Before doing anything else: do not erase, reformat, or run First Aid again on that drive. Those can make recovery harder.


Here are some steps to try to gain access to your data:

  • Open Terminal and run: diskutil list. Confirm the identifier is really `disk2s2`, then try: diskutil mount disk2s2.
    • If it’s encrypted, try unlocking it: diskutil apfs unlockVolume disk2s2
    • If it asks for a password and accepts it but still won’t mount, that means the filesystem is readable but the mount metadata is damaged — perfect case for recovery tools.


There are some free recovery tools that can be used to copy files:

(NOTE: If this data is critical to you, I highly recommend using either a paid version of a recovery tool or using a dedicated recovery service.)

  • PhotoRec (part of TestDisk) – ugly UI, but extremely powerful and 100% free
  • DMDE Free – allows limited free file recovery per session
  • R-Studio Demo – lets you verify recoverability before deciding
3 replies
Question marked as Top-ranking reply

Jan 9, 2026 10:03 AM in response to ninjaphrodite

Yes — you likely can recover your files without paying for Disk Drill, and based on what you described, the data is probably still there. The “can’t be unlocked” message strongly suggests the drive is encrypted (APFS or HFS+), and macOS is failing during the unlock/mount step rather than the data being gone.


So why this is happening? From your symptoms:

  • “Can’t be unlocked”
  • “Internal state error”
  • Disk Drill sees files
  • System Info shows wrong free space


This points to: Corrupted APFS encryption metadata, not dead storage. The drive is readable at the block level — that’s why recovery tools can see files.


Before doing anything else: do not erase, reformat, or run First Aid again on that drive. Those can make recovery harder.


Here are some steps to try to gain access to your data:

  • Open Terminal and run: diskutil list. Confirm the identifier is really `disk2s2`, then try: diskutil mount disk2s2.
    • If it’s encrypted, try unlocking it: diskutil apfs unlockVolume disk2s2
    • If it asks for a password and accepts it but still won’t mount, that means the filesystem is readable but the mount metadata is damaged — perfect case for recovery tools.


There are some free recovery tools that can be used to copy files:

(NOTE: If this data is critical to you, I highly recommend using either a paid version of a recovery tool or using a dedicated recovery service.)

  • PhotoRec (part of TestDisk) – ugly UI, but extremely powerful and 100% free
  • DMDE Free – allows limited free file recovery per session
  • R-Studio Demo – lets you verify recoverability before deciding

USB wont mount, how can I recover data?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.