8 Replies Latest reply: May 15, 2009 5:27 AM by The hatter
Rick Billings Level 1 Level 1 (0 points)
Several Days ago, during some routine maintenance procedures (i.e. Starting up from Drive Genius 1.5.3 disk and repairing permissions, repair and defrag), I discovered that I have the dreaded "Invalid B-Tree node size" error. Drive Genius didn't tell me this, Disk Utility did.

I have done some research on this error, and have not found very much in the way of something helpful. Most of the postings and information across the internet, including from this site, indicate that when a hard drive has this problem it becomes un-bootable.

Well, that is not the case for me. I have seen a great improvement in performance since my routine maintenance and my Mac is running Great! But, when I run Verify Disk with Disk Utility, it indicates that I still have the problem.

I have tried Single User Mode to run FSCK various times using different combinations of the -y & -f flags. It does nothing more than Disk Utility. It reports the error, but does not fix it.

_*Does anyone know how to fix this error?*_
*Is it possible to fix the error without initializing?*

+Meanwhile, I'm doing some serious back-up incase this gets worse.+

G5, Mac OS X (10.4.11), Dual 2 GHz PPC G5, 1.5 GB DDR SDRAM, HDD 150 GB
  • The hatter Level 9 Level 9 (60,790 points)
    Apple has tech note on that error message. The recommendation from 99% users here and elsewhere is you need your backups, and you need Alsoft Disk Warrior (never owned Drive Genius) or TechTool Pro (5.04) should be fine.

    You never want to use older version of even Disk Utility to repair permissions and drives than what you have running.

    Never, ever, rely on just Apple First Aid. It misses potential errors until they are worse and can't be fixed.

    I would not trust a drive fully even after repairing. Just to preview the volume and recover files.

    I'd install a fresh copy of OS X on a new or different drive and then import or migrate or reinstall apps, and then data.

    I feel it is better for performance to keep the OS and apps separate. To always have a backup image that you can restore from, or boot from. Two backup sets for every drive.

    Your copy of Drive Genius may be out of date or not the most current.
  • japamac Level 7 Level 7 (24,390 points)

    No on Drive Genius, YES for Disk Warrior. I hear DG2 is better, but I gave up on DG1. It was causing too many problems....

    Disk Warrior will invariably fix that which others can't.

    Booting to your OS X install disc and running Disk Utility 3 or 4 times (consecutively) is worth a shot.

    If, after that, the error persists, use Disk Warrior.
  • Rick Billings Level 1 Level 1 (0 points)
    The hatter wrote:
    Apple has tech note on that error message.

    Do you know, off hand, which tech note it is?
    I would not trust a drive fully even after repairing. Just to preview the volume and recover files.

    Do you think that it is a problem with the HDD itself and not just from a improper shutdown...?
    After reading your post, I realized that I have had to reformat this drive about once/year for the last 3 or 4 years.

    It sounds like it is time for me to put DG to rest and get DW; and maybe a new HDD.
  • The hatter Level 9 Level 9 (60,790 points)
    You mean you use computers but can't find Apple's famous technotes? even veterans have trouble though - hint, it has gotten harder, there use to be a single page with the day's latest updates and changes, now, everything is RSS, a technology I don't subscribe to.

    Disk Utility will never put Alsoft or MicroMat out of business.

    Disk drives need attention.

    Changes in the partition table are best handled by reformat, and while some may tell you this is overkill, if they looked under the hood, there are strong reasons in favor.

    Zeroing a drive from time to time, or better yet, do a media scan (TechTool Pro seems best after years of using various utilities).

    Once a year is better than some. The upgrade to 10.5.x was a good time, trouble is it was ".0" and not to be trusted, and not reliable. 10.5.6 isn't perfect either according to an article on MacFixit, but I applaud seeing 10.5.6 DVDs out there (would like to see another one or two as long as there is Leopard OS).

    One problem is reparing isn't perfect.
    The other, that there are sectors on a drive that only get tested and created during a reformat, not from erasing a volume.

    A new hard drive on a regular basis, and retire the older drive to archive and backup duties is always a good idea.

    Thanks to Google and search capability -
    Resolve startup issues using fsck
    Permissions (which I mentioned above)

    MacFixit Index of Tutorials (subscription for most)
  • Rick Billings Level 1 Level 1 (0 points)
    Ok. here's the latest.
    I've read all of the tech-notes.
    I've tried booting from the install disc to run Disk Utility - Same results:

    *Invalid B-tree node size*
    *The volume G5 HD needs to be repaired.*
    *Error: The underlying task reported failure on exit*

    I tried starting up in safe mode, but the computer powers down after beginning the start-up. The same thing happens when starting up in Verbose Mode, but a quick read of the report as it flashes on and of the screen indicates something about a "power loss"? I'm not sure what that's all about.

    It will start up in single user mode to use FSCK, but as I mentioned before, the results were the same as with Disk Utility.

    My conclusion is that it would be best to get a new HDD, Reformat this drive, and get DW for future use.
  • The hatter Level 9 Level 9 (60,790 points)
    I have always said Apple First Aid is insufficient, won't put MicroMat or Alsoft out of business, and don't wait for DU to get to this point, use DW (or TechTool Pro). It is sometimes recommended to let DU have first go at it, but follow up and still run DW.

    Always good to have spare drives, but the problem is HFS+ and OS X, usually, even memory errors (system ECC can still have errors and wrote garbage or the ECC memory in the disk drive could) but usually just a reformat of a drive - or even Disk Warrior - is enough.

    A lot of errors can be dealth with by removing temp and cache files.

    The DU "underlying task" tech note:
  • bubbajeph1 Level 1 Level 1 (0 points)
    Don't even think of taking this problem to an Apple Store. I went to MacArthur Mall in Norfolk Virginia with my external firewire hard drive that has ALL my iTunes files on it with this Invalid B-tree node size error message. They would not even look at it. Totally blew me off. I've been a Apple user since the Apple IIc. I've had several Macs since my MacSE with two 400k drives. I'm totally ******! I've ordered Disk Warrior. I am unable to correct the error message with Disk Utility from my start up CD. Tech Tool Pro just spins.
  • The hatter Level 9 Level 9 (60,790 points)
    Don't boot from a CD or DVD. Boot from an alternate, emergency only, system drive. One that has the same / latest version of OS X.

    And two (minimum) backups of everything, three is even better.

    If you have used and been around Macs, Disk Warrior has been recommended for at least last nine years as #1. And essential, though TechTool Pro 4.62 or new 5.0.4 should also be fine and has features DW lacks.

    TTPro may have trouble because the directory is so bad. A severe corrupt directory can PREVENT booting from even a CD. Sometimes the drive needs to be OFF and only turned on after the system is up and running, which can mean pulling and putting in a FW/USB case or docking station if it is an internal drive.