I have two USB sticks that no longer mount or can be repaired with Disk Utility, and I know it’s because I removed them prior to their being unmounted by the Finder. How can they be restored?
iMac 21.5″ 4K, macOS 13.7
You can try using a data recovery app such as Disk Drill or Stellar Data Recovery. Usually they allow you to try out the product to see if they can discover any files, but you may need to pay in order to actually recover the files found.
If the USB stick was using the HFS+ file system (aka MacOS Extended), then you could try using the paid app Disk Warrior to attempt to repair the file system. However, if there is a hardware issue involved, then DW will refuse to make any modifications.
I would highly recommend you start some sort of backup strategy so you can recover lost or damaged items from a backup. Apple provides Time Machine for free with every copy of macOS.
Can a Corrupted USB Stick Be Fixed After Premature Removal?
Yes! If your USB stick was corrupted due to improper ejection (unplugging without safely removing it), the data may still be recoverable—even if Disk Utility fails to repair it. Here’s what you can do:
1. Try First Aid in Disk Utility (Mac)
2. Reformat the USB Drive (If Data Isn’t Critical)
3. Data Recovery Software (If Files Are Important)
If the USB contains valuable files, avoid reformatting immediately—use a data recovery tool like 4DDiG Data Recovery to rescue files before attempting fixes.
If the USB Still Won’t Mount—Try 4DDiG Partition Manager. This Tool may help.
You can boot that Intel iMac into Recovery and run Disk Utility First Aid against that USB stick — provided it can still mount. It may or may not fix the corruption. Caveat Emptor.
dsoileau wrote:
I’m disappointed that Apple doesn’t provide recovery for such an easy error. Any third-party products worth purchasing/using? Any Terminal options?
Sorry? How is Apple supposed to provide “recovery” for that? The drive was removed while it was being written to. That resulted in corruption… garbage… scrambled bits.
USB flash drives should never be used for primary storage of anything. They are too susceptible to corruption and data loss. That’s true regardless of what computing platform you use.
I made a mistake and was in too much of a hurry. Still, I used Norton Utilities as far back as the early 90s, with a floppy-based boot-up, no less, and been able to recover/restore files from hard drives and removable media (floppy, Syquest, Zip, etc., prior to USB). Yes, I consider the present lack of recovery options appalling.
Magnetic media and NAND flash storage are massively different kinds of technology. As others have mentioned, this has nothing to do with Apple - there is no company, and I mean none at all, nada - that can recover media from an unmountable flash drive.
If you can mount the drive somehow, then you may be able to partially recover data - but anything that was garbled because of you pulling the drive is unrecoverable. Again, that's the nature of flash storage. If nothing else you might be able to erase the drive and use it again.
They probably can't be. At least I've never recovered one once they fail.
I’m disappointed that Apple doesn’t provide recovery for such an easy error. Any third-party products worth purchasing/using? Any Terminal options?
As Tim explained, your issue has nothing to do with Apple.
There is a huge difference between physical media and flash storage.
FWIW, as VikingOSX mentioned, there's zero chance of recovering a flash drive if it won't even mount.
USB stick corrupted by premature removal—fixable?
