Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

A folder caller LOST.DIR keeps appearing on my external drive. What is it / how can I make it go away?

share|improve this question
What are the contents of LOST.DIR? What kind of drive, and how is the drive formatted? – Chealion Oct 8 '09 at 23:15
SD card reader, USB mass storage, FAT32. It's always empty. – Isaac Waller Oct 8 '09 at 23:41
is this on your Android "external drive"? – sirlancelot Oct 20 '09 at 2:24
up vote 2 down vote accepted

LOST.DIR is something mac disk repair looks for and will ask about as part of it's repair process. If it's related at all to the standard lost+found, then it's a special file that holds all the corrupted or orphaned files found during a file system check.

My guess is Wil is right, something is checking your drive and finding a problem it wants to make note of in LOST.DIR. I think this sort of thing is more likely to happen with Macs on non-HFS drives.

share|improve this answer

If I am wrong, someone else please correct me - but my guess is that upon connecting your external drive, OSX is doing some sort of scan and detecting corrupt / partly deleted files and it automatically attempts a recovery.

I would advise that you do a full disk scan on it and check for bad sectors.

share|improve this answer
Not sure why someone down-voted this. I'm pretty sure this is correct as well, though I've not been able to verify it. What you could try is copy off the files, repartition and reformat the drive and copy it back. – emgee Oct 20 '09 at 2:27

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.