All of a sudden HDD not readable..

[HaxMan]

Hey guys,

Desperate need for help right now.. Everything in my build has been running perfectly until this morning. I'm using two SSD's one with Lion OS and one with Windows 7 OS. And then I'm using one WD Caviar Green 2TB HDD formatted to exFAt for all of my files, downloads, media. Well I turned on my computer this morning and all of a sudden the HDD is "unreadable". I've tried opening it on both OS's, it's telling me I need to format the drive. Does anyone know how to fix this without losing everything on it? Or am I screwed?

The rest of my build is in my signature. Any help appreciated

 

[Koalaman]

Try booting with -v -f -x and tell me what it says.

 

[HaxMan]

The text flys by too quickly I don't know how.. I noticed in Disk Utility in the Log when I try to repair disk it says invalid sector size:0 Dunno if that means anything. The disk also appears to be in MS-DOS format now.. no idea why

Edit: The name of the drive also changed to "disk1s2"

 

[HaxMan]

I'm prepared to wipe it if I have to.. I'd just like to know how this happened or if it'll happen again. Faulty HDD?

 

[Koalaman]

I would zero it and try again. It may or may not be faulty.

 

[rmat]

Hey HaxMan, my drive all of a sudden did the same thing yours did. I had the same setup... one drive with OS X, one with Windows 8, and a shared storage drive formatted exFat. Did you find a solution to your problem or did you end up having to wipe it?

 

[Going Bald]

Your problem is the ExFat format. It is not really stable as any error in read/write can cause the drive to be unreadable.
If you do not have 4Gb+ sized files there is no reason to use ExFat. Use HFS+, NTFS or FAT32 format for storage drives.

What you can try doing is open disc utility in OS X and attempt to repair the drive. If this fails, you willl have to erase/reformat the HDD.

 

[dsms]

I had the same problem, my exFAT volume was gone, Disk Util said "invalid sector size: 0" and it was not able to repair the volume.

This worked for me: Open up Terminal and type

[B]sudo fsck_exfat -d [COLOR=#3E3E3E]disk1s2[/COLOR][/B]

, assuming that disk1s2 is the volume in question.

After fsck_exfat has finished, it asks you "Main boot region needs to be updated. Update?". Type "Yes" and hit Enter.

After that, go back into Disk Util, now the right name of your volume should appear instead of "disk1s2". Now, repair the volume, this time it should work. Disk Util will print out the following:

Checking main boot region.Checking system files.
Volume name is ORIGINAL_NAME.
Checking upper case translation table.
Checking file system hierarchy.
Checking active bitmap.
Rechecking main boot region.
Rechecking alternate boot region.

The volume ORIGINAL_NAME appears to be OK.

I suspect in my case a running application which had opened files on the exFAT volume, which has not been shutdown properly when I rebooted Mac OS X.

 

[zappzerapp94]

You made my day, dsms!

Wow, this worked great for me!
I already hat this error half year ago and didn't know, what to do, so i formated my disk (at this time there were every data backuped on an extra storage, so the only bad thing was the time i had to wait), but today i thought first, that my 600gb data were lost.
Thank you very much

 

[lexone]

I had the same problem, my exFAT volume was gone, Disk Util said "invalid sector size: 0" and it was not able to repair the volume.

This worked for me: Open up Terminal and type

[B]sudo fsck_exfat -d [COLOR=#3E3E3E]disk1s2[/COLOR][/B]

, assuming that disk1s2 is the volume in question.

After fsck_exfat has finished, it asks you "Main boot region needs to be updated. Update?". Type "Yes" and hit Enter.

After that, go back into Disk Util, now the right name of your volume should appear instead of "disk1s2". Now, repair the volume, this time it should work. Disk Util will print out the following:

Checking main boot region.Checking system files.
Volume name is ORIGINAL_NAME.
Checking upper case translation table.
Checking file system hierarchy.
Checking active bitmap.
Rechecking main boot region.
Rechecking alternate boot region.

The volume ORIGINAL_NAME appears to be OK.

I suspect in my case a running application which had opened files on the exFAT volume, which has not been shutdown properly when I rebooted Mac OS X.

Ran into this same exact issue out of nowhere...thx for providing this fix! Worked perfectly!