13 Replies Latest reply: Feb 7, 2010 7:21 AM by mecredis
davidmarc Level 1 Level 1 (0 points)
I installed SL last night on iMAC; came in today and TIme Machine can't see external (MAC HFS formatted) HD. After a bit of fussing, I find my external hard drive is trashed. When I plug the HD into any Mac I now get this message "The disk you inserted was not readable by this computer"; and Disk Utility sees it but when I try to repair disk I get:

Verifying volume “disk1s2”
Checking Journaled HFS Plus volume.
Invalid record count
The volume could not be verified completely.
Error: This disk needs to be repaired. Click Repair Disk.


and when I try to "Repair Disk" I get the same: invalid record count, and the unhelpful comment ...

"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."
(Since my disk is unreadable, it is a challenge to back up)

I conclude that either I was real unlucky and my external HD crashed both partitions at the some time with a weird R/W problem, or more likely, the SL installation trashed my Time Machine backup drive.

Apple Support said SL installation had nothing to do with it. I suspect otherwise. Anyone else see this?

iMac, Mac OS X (10.6)
  • 1. Re: SL installation leads to Time Machine HD
    Scott Radloff Level 6 Level 6 (14,490 points)
    davidmarc,

    Snow Leopard has treated all of my external drive, in all their flavors, quite well. And, yours is the first post I have seen regarding external drive disk errors.

    If I enjoyed betting, it would be that this is just an unlucky coincidence.

    That said, it might help to know your drive's make, model, and size. I do know that, at least in the case of some Western Digital drives, updated firmware is available that provides better compatibility with Snow Leopard.

    Scott
  • 2. Re: SL installation leads to Time Machine HD
    epetrone Level 1 Level 1 (0 points)
    I have a 15'' Macbook Pro and I have the exact same problem. It also won't let me restore some files like iPhoto Library (permissions???).

    The story is after an erase & install of SL, and everything running fine for 2 days, all of a sudden Time Machine goes bonkers and says "Error: This disk needs to be repaired. Click Repair Disk." After completeing the repair, it says " Updating boot support partitions for the volume as required. 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."

    Any ideas? Because I need to get those photos back! Family first as they say..
  • 3. Re: SL installation leads to Time Machine HD
    Scott Mahrer Level 1 Level 1 (65 points)
    My Firewire External HD was unplugged during Snow Leopard install, as suggested. I too am getting the "The disk you inserted was not readable by this computer" error. Disk Utility does "see" the drive, but will not allow a repair. I'm concerned as I plan to install SN on Macs that utilize more external drives. Can't afford to lose the data on this drive in question, either!
  • 4. Re: SL installation leads to Time Machine HD
    whatstin Level 1 Level 1 (0 points)
    I'm having the same problem. Snow Leopard (developer edition - 10.6). Western Digital MyBook 500GB drive devoted to Time Machine backups. Disk Utility recognizes it, but it won't mount.

    The drive worked fine as of a few weeks ago. Something changed between August 16th and now that's causing the drive not to mount. Same lame error:

    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.
  • 5. Re: SL installation leads to Time Machine HD
    Noiseconformist Level 1 Level 1 (0 points)
    I just ran into the same problem:
    I've an external WD 500GB FW 400/800 2.5" Disk split into two partitions.
    On one I'm running my test installation of 10.6 the other holds a backup of my 10.5 working system.
    Now I can't access the backup partition.
    Messages are exactly the same as above.
    I tried to repair both under 10.5.8 and 10.6 but no luck.
    Backing up and re-formatting is tough since the disk is not accessible - as one of you already stated above.
    What gives?
    Michael.
  • 6. Re: SL installation leads to Time Machine HD
    Noiseconformist Level 1 Level 1 (0 points)
    what I tried now:
    Rebooted into 10.6 on this disk.
    Got a pop-up saying "SL can't repair this disk. Run disk utility ... " But I could access this disk via finder.
    I rebooted again and no more error messages.
    Disk partition in question appeared to be fine.
    Then, out of curiosity I ran disk utility and verify on this particular partition.
    Bang - again, the same messages like above ... can't repair, backup etc. etc.
    I'm rebooting again now to check ...
  • 7. Re: SL installation leads to Time Machine HD
    Noiseconformist Level 1 Level 1 (0 points)
    +Verify and Repair volume “Boskop-BAK”+
    +Checking Journaled HFS Plus volume.+
    +Checking extents overflow file.+
    +Checking catalog file.+
    +Invalid sibling link+
    +Rebuilding catalog B-tree.+
    +The volume Boskop-BAK could not be repaired.+
    +Volume repair complete.Updating boot support partitions for the volume as required.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.+
  • 8. Re: SL installation leads to Time Machine HD
    Pondini Level 8 Level 8 (38,720 points)
    Do you have backups of that data? If not, you may be learning the value of regular backups the hard way.

    It is possible that +Disk Warrior 4.2+ may be able to repair what Disk Utility can't. It's about $100, and of course there are no guarantees.

    It's also possible that a +data recovery+ app or service may be able to recover some of the data. These are expensive, too, and again no guarantees, although some are reported to have a free version that will tell you whether there's anything it can recover, and perhaps let you recover one file. You'll need a second external disk for it to put the recovered files on.

    +Data Rescue II+ seems to be mentioned most often here. I haven't used any myself, so can't recommend one way or another. Try Google, VersionTracker.com, or MacUpdate.com for +data recovery.+

    Since you probably need another disk anyway, do yourself a favor: get one that's at least twice the size of all your data (plus however much you'll add in the foreseeable future), but preferably 3 or 4 times. Then once this is sorted out, begin regular backups via Time Machine and/or CarbonCopyCloner, SuperDuper! or the like.
  • 9. Re: SL installation leads to Time Machine HD
    Noiseconformist Level 1 Level 1 (0 points)
    In my case the troublemaker is a CCC clone (on one of the two partitions) of my 10.5.8 System.
    The other partition (a test install of SL) is fine.
    Funnily enough I can boot from this clone, but I can't access it if it's just mounted on a different system (like the local 10.5.8).
    I'm sure the disk itself is ok but its contents on this particular partition appears to be garbled.
    Hence my concerns how this could happen.

    Michael.

    PS: Time Machine is great but also gave me some issues to solve (missing files etc.)
  • 10. “Updating boot support partitions for the volume as required.”
    Michael Lowry Level 1 Level 1 (5 points)
    I upgraded to 10.6 as soon as it came out. I have my Time Machine backup on an external 1 TB WD MyBook drive connected by FW 800. I had no problems with the backup until today. When I connected the external drive, it did not mount automatically even though for several minutes I could hear drive activity.

    I ran Disk Utility and tried to mount, and the repair the disk:

    2009-11-30 16:13:05 +0100: Mount of “Draco” failed
    2009-11-30 16:13:08 +0100: Verify and Repair volume “Draco”
    2009-11-30 16:13:08 +0100: Starting repair tool:
    2009-11-30 16:13:08 +0100: Volume repair complete.
    2009-11-30 16:13:08 +0100: Updating boot support partitions for the volume as required.
    2009-11-30 16:37:03 +0100: 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.
    2009-11-30 16:37:03 +0100:
    2009-11-30 16:37:03 +0100: Disk Utility stopped repairing “Draco”: 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.

    When the "Updating boot support partitions for the volume as required." message appeared, the drive was busy for several minutes. After that, the disk was mounted in read-only mode. This means that I am no longer getting up-to-date backups of my files.

    I would be grateful if anyone could provide a solution to this problem.
  • 11. Re: “Updating boot support partitions for the volume as required.”
    Michael Lowry Level 1 Level 1 (5 points)
    After reformatting, the drive works fine again. It sure would be nice to see some information about why this problem happened.
  • 12. Re: SL installation leads to Time Machine HD
    aneesh.parekh Level 1 Level 1 (0 points)
    I keep getting the same error and have reformatted several times. This works fine for a while and then the same error keeps reappearing (WD MyPassport Essential 1TB)
  • 13. Re: SL installation leads to Time Machine HD
    mecredis Level 1 Level 1 (0 points)
    I just wanted to chime in and confirm that I'm having this problem. I've actually observed it 4 (?!!) times. I replace the drive thinking I was unlucky. Then after a couple of weeks of TM working perfectly, it failed and I got the "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." message using Disk Utility.

    I then had two external hard drive enclosures with two broken HD drives in there. After going a year without backups I decided to bite the bullet and set up an A/B backup scheme with the two enclosures and new 1TB drives since they're now relatively affordable. After a couple of weeks, same error. Getting used to it, I just switched the connection to the new drive and went on my way. 6 months later, I'm getting this error with Disk Utility again. The only data at risk is my backup data, and so it isn't of huge importance that I recover it (unless my machine crashes between now and when I resolve this problem).

    It sounds like there's a real problem with how OS X or TM treat large external drives.

    I'm now looking into a network disk / rackmount option with TM support because this is fairly ridiculous.

    Message was edited by: mecredis