exFAT volume often gets corrupted

The fsck_exfat method you proposed worked for me, too - THANK YOU!!! Strikes me as a very serious shortcoming that Mac OS X 10.8.4 managed to corrupt an exFAT partition that I had only created because it was proposed by Disk Utility (good idea for Windows interchange, no?), and that had only ever been touched by Mac OS X, and only for a couple hours, writing some large 10 GB video files, around 300 GB all in all. Good I got them back!

Hi, I also have an Exfat drive that went corrupted, I checked all different kinds of solutions , especially the one from neo_amiga who looked very promising, unfortunately for me the things went a bit differently.

Here's a screenshot of my disk info from the Disk Utility, i hope it helps (sorry for the french i'm sure you can compare with your own disk to understand the table better 🙂) it stills says the disk is fixable

if i got this right, the index isnt just corrupted but completely missing.. if some has an idea of what to do 🙂

Did anyone discover a solution for this problem? Running the command:

sudo fsck_exfat -d disk3

returns the following script:

Opening /dev/rdisk3

** Checking volume.

** Checking main boot region.

fsck_exfat: Could not read boot region

** The volume
could not be verified completely.

Previously tried to run diskutil verifyVolume /dev/disk3 and got the following script:

Error starting file system verification for disk3: Unrecognized file system (-69846)

Trying to recover a Seagate expansion hard drive that appears in diskutil and in the Disk Utility app, but all options for repairing the disk are greyed out. I've tried many of the flows suggested in this thread but I'm still running into this main error above - that the volume could not be verified completely. Thanks in advance!

Could be the exFAT implementation that Mac OS X uses to format the drive. Everytime I tried to use that format, formatted on a Mac, no Windows computer could read that drive. When formatted exFAT on a windows PC both Mac and Windows could read and writer to it.

I suggest you dump the exFAT partition, esoecially it is using the GUID partition table.

When I briefly had a Boot Camp partition and Win 7 installed on my MBP I could read and write to the Mac partition from Windows and could read and write to the Win partition from the Mac side. At least I think I could. Now that may be something that was included in Boot Camp V4 and you may be running an older version of BC. Not sure.

32 GB thumbdrive, formatted as exFAT by Windows. That drive is dedicated to only shared data so should not be corrupted by the partition-mapping.

And very portable, although slow-ish.

Bus-powered USB drive also possible -- light and small. Bus-powered is bad for backups but seems OK for data-share.

Made the difference for me, at least. But that is not a guarantee for you.

Good luck.

Ok sorry I remembered wrong then. No need to have Windows in it own partition on my Mac. I have windows PCs for that.

zdenekfromnew york wrote:

I got latest of version of BC and cannot write to HFS+ (Mac) drives, read only.

exFAT, well I got it formatted by Mac probably. Ill try format it by Windows then and I'll see how that goes but I dont think there will be any difference.

Had some issues with corrupted exFAT partition that Disk Utility said it couldn't repair.

2012-09-06 21:35:31 +0200: Verify and Repair volume “disk0s4”

2012-09-06 21:35:31 +0200: Starting repair tool:

2012-09-06 21:35:31 +0200: Checking file system2012-09-06 21:35:31 +0200: ** /dev/disk0s4

2012-09-06 21:35:31 +0200: Invalid sector size: 0

2012-09-06 21:35:31 +0200: Volume repair complete.2012-09-06 21:35:31 +0200: Updating boot support partitions for the volume as required.2012-09-06 21:35:31 +0200: Error: Disk Utility can’t repair this disk. Back up as many of your files as possible, reformat the disk, and restore your backed-up files.2012-09-06 21:35:31 +0200:

2012-09-06 21:35:31 +0200: Disk Utility stopped repairing “disk0s4”: Disk Utility can’t repair this disk. Back up as many of your files as possible, reformat the disk, and restore your backed-up files.

2012-09-06 21:35:31 +0200:

Looked like crazy on the net for solutions but couldn't find any. I started to poke around in the terminal and ran this:

fsck_exfat -d disk0s4

The -d flag is the debug flag and it gave me hope. I saw all my files flashing by and after a while I got this question:

Main boot region needs to be updated. Yes/No?

I hesitated for a long while but realized that I didn't have any other option. I picked yes and it said that it repaired the drive. It didn't appear on the desktop though. I ran fsck_exfat again and now it said that the disk was ok. I fired up Disk utility and tried to repair the drive there once again and now disk utility could repair it! =)))

Just wanted to share this lil advice since it seems common that exfat partions gets corrupted in OSX. I'm running 10.8.1 on rMBP here. I have no idea why Disk Utility doesn't call fsck and instead says that the disk can't be repaired. The tools for repairing it is in the OS and apparently and obviosusly it was fixable (...in my case).

Cheers

NEO_AMiGA you just spared me a whole lot of grief!

I didn't realize that exfat drives corrupt easily and that there was a simple tool to fix it (fsck_exfat). I thought I had more serious issues with my partition table so tried to rebuild it using testdisk. Unfortunately i must have screwed up the hybrid mbr since bootcamp is now not bootable. One problem at a time...

Neo_AMiGa Great Postimg!

you spare me from the painfull loss of critical files. I am abandoning xfat. I am gald I steped away from the problem and was checking for possible solutions this AM. thanks

Neo_AMiGa Great Posting!

I just recovered all my critical data. Had no backup.

Thanks a lot

NEO_AMiGA you are awesome! You have my gratitude.