October 30, 2014

Mac OS X Bug: ExFAT Hangs Spotlight and Time Machine

I’ve had terrible issues with Mac OS X never completing Spotlight indexing and Time Machine backups. I was pulling out my hair until I decided to check the console log. That’s when I saw this: Thousands of mdworker errors, with a dozen appearing every second. What could it mean?

mdworker: (Warning) Import: Bad path:

There was no more information in the console or inspector. I immediately turned to the Google and found some  suggestions that ExFAT was at fault.

I love ExFAT. It’s a great filesystem for removable media since it’s readable and writable on both Mac OS X and Windows and scales gracefully with today’s larger storage devices.

But Mac OS X apparently does not love ExFAT. Specifically, it appears that mdworker, the background task used by both Spotlight and Time Machine, chokes on ExFAT volumes. This is the source of the “bad path” error: Mdworker seems to continually retry doing something with ExFAT volumes. And mdworker never stops.

I’m not sure how to fix this issue, though I can offer a suggestion to help: Eject any ExFAT volumes before initiating a Time Machine backup or Spotlight indexing run. For me, this immediately halted the mdworker warnings and allowed Spotlight to complete its work.

Note: This issue appeared in November 2013 in Mac OS X 10.9 “Mavericks”. Let’s hope Apple fixes it in the future.

  • Geoff Arnold

    Why not just exclude the ExFAT volume in Spotlight and Time Machine preferences?

  • edddeduck

    Just add a file called “.metadata_never_index” to the root of all your ExFAT partitioned volumes. It prevents Spotlight from processing that volume.

    You can’t create files starting with dot in the Finder so do it via the terminal.

    1. Open the terminal and go to the root of the ExFAT partition.
    2. type the line below exactly and pressing enter.
    touch .metadata_never_index

    3. Check it was created by typing in:
    ls -la

  • Eric

    Well, I have the same problem but it didn’t happen before i upgrade to osx 10.9…. it doesn’t sound like a solution for me to exclude my external HDD form spotlight indexing,…

  • http://www.facebook.com/profile.php?id=1331532608 Thomas J Wright

    “Permission Denied”

  • Asincrono

    Same situation here (iMac with OS X 10.9 out of the box)… the same “05/04/14 22:58:06,293 mdworker[5585]: (Warning) Import: Bad path:” and mdworker running non stop over the exfat partition :S

  • Asincrono

    sudo touch .metadata_(…)

  • jerrykrinock

    I was getting these same stupid entries in my Console. The culprit was: my 4th Gen iPod Shuffle. Arghhhh!! Disconnecting the Shuffle stopped the console. If it happens again, I’ll try to “don’t index” things, but you’d think Apple would have built that in to their own device.