One volume on external hard drive not mounting

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Level 1

25 points

One volume on external hard drive not mounting

Hi all, thanks in advance for any help. I have an external hard drive connected via FW800 with 2 volumes on it and one of the volumes will not mount. It was fine until just recently. System profiler see it as not mounted, disk utility sees it but will not mount it, repair disk in first aid says the disk is fine. I've repaired permissions but no luck. How can one volume be fine and the other un-mountable ? Any thoughts on what else I should do ? I have a second one of these drives, if I daisy chain it through the first one, it works fine.

17" PB G4 1.67Ghz 2Gig, Mac OS X (10.5.8), 3rd Gen Nano iPhone 4 32G

Posted on May 1, 2011 10:13 AM

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Answer 1

a brody

Level 10

82,841 points

May 2, 2011 9:22 AM in response to RandyInBC

So in other words it fails to work when it isn't daisy chained?

Is it plugged in to an external (to the computer) power source when the issue is happening?

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Answer 2

RandyInBC Author

Level 1

25 points

May 2, 2011 9:53 AM in response to a brody

Hi Brody. The troubled drive has 2 volumes on it, 1 volume will mount and 1 will not. It has it's own power source that is working. The second drive I mentioned is my girlfriend's backup drive, I daisy chained it through mine which is plugged directly to the computer just to see if it would work and that the FW800 port was working ok, it appears to be. System Profiler see both volumes with full details (name, volume size, file system), the only difference here is 'Mount Point' is blank on the troubled volume. The drive is a 1T Western Digital 'My Book Studio For Mac" if this helps. Any other info needed ? please ask.

Thanks again

Randy

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Answer 3

May 2, 2011 12:26 PM in response to RandyInBC

One thing you can try in Disk Utility is to select the physical device in the volumes window (not the actual volumes) and click Verify Disk to see if it verifies both volumes. You may have done that already, and if so, then "never mind" but let us know.

Another off the wall thing to try is to swap FW800 cables. While I can't see how a cable would prevent one volume from mounting, I have seen stranger things occur.

I didn't get a clear feeling that you were able to mount both volumes when daisy-chained through the other drive ("seemed to work" was kind of hedging).

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Answer 4

RandyInBC Author

Level 1

25 points

May 2, 2011 1:01 PM in response to old comm guy

Hi OC Guy, I've tried in disk utility mounting both the drive and individual volumes but no luck. I've also tried swapping cables. There are no issues with the 2nd drive, both it's volumes mount fine, either daisy chained or plugged directly to the computer. My girl friend will be over Tuesday evening and I will try plugging my troubled drive into her computer and seeing what happens.

Thanks for helping out

Randy

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Answer 5

May 2, 2011 3:36 PM in response to RandyInBC

This is definitely a puzzle, as a volume (partition) showing in Disk Utility, though grayed out, should be able to be mounted. The "other computer" comparison is definitely a good troubleshooting strategy.

Just a quick thought: when you select the drive itself in Disk Utility, what partition map scheme is indicated in the information area at the bottom?

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Answer 6

May 2, 2011 6:35 PM in response to RandyInBC

RandyinBC, I am having the EXACT same problem with a Seagate external drive. I have a second drive I'm using for my backup but I can't daisy chain them. I've tried everything mentioned above and having the same issue you are. Hopefully there is a solution. i have a lot of photos I need to access and can;t.

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Answer 7

May 2, 2011 7:24 PM in response to RandyInBC

This is the info on my drive. I'm wondering if the "Owners enabled: No" has somethign to do with it. The drive partition that mounts has a "Yes" next to it.

Disk Identifier : disk1s2

Mount Point : Not mounted

File System : Mac OS Extended (Journaled)

Connection Bus : FireWire

Device Tree : /PCI0/RP04@1C,3/FRWR@0/node@20370002a12f88/sbp-2@c000/@0:2

Writable : Yes

Capacity : 100 GB (107,374,182,400 Bytes)

Owners Enabled : No

Can Turn Owners Off : Yes

Can Be Formatted : Yes

Bootable : Yes

Supports Journaling : Yes

Journaled : No

Disk Number : 1

Partition Number : 2

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Answer 8

RandyInBC Author

Level 1

25 points

May 2, 2011 9:52 PM in response to old comm guy

I got it FIXED YEAH !!!! Not sure what it was that caused it or how it happened but... I forgot about trying Disk Warrior on it, and it did the trick. I had it check the directories and 2 files/folder were critically damaged, Disk Warrior rebuilt them and now the volume is mounted.

Thanks for everyones help.

Randy

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Answer 9

May 2, 2011 11:08 PM in response to RandyInBC

RandyInBC wrote:

I got it FIXED YEAH !!!! Not sure what it was that caused it or how it happened but... I forgot about trying Disk Warrior on it, and it did the trick. I had it check the directories and 2 files/folder were critically damaged, Disk Warrior rebuilt them and now the volume is mounted.

Thanks for everyones help.

Randy

Hooray for Alsoft!

I wouldn't have thought of that since I thought you had gotten a clean bill of health from Disk Utility.

DW has come through for me in several nasty pinches over the years with flying colors. I now do a rebuild of my many volumes' directories (many ... long legacy story) when I do my five-week swap of the internal backup drive with the safe deposit box. It is time well spent, I think ... good insurance.

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