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Data on Disk inaccessible - suddenly unformatted

Discussion in 'Windows XP' started by jaymax, Jun 17, 2009.

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  1. jaymax

    jaymax Thread Starter

    Joined:
    May 28, 2009
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    Hello,

    {An upfront apology - in not been able to format some of the tables below but included them nevertheless for completeness}

    Win 2K Prof. SP4

    Multi Disk System

    All NTFS

    Reinstalled O/S on one drive - Master on EIDE channel on MOBO

    Slave drive on same channel appears normally in POST, but in "My Computer" Listing name appears as "Local Disk (I)" Details of disk size absent. This drive previously had 3 partitions.

    Master 58.6 GB; Slave 500 GB, both disk type Basic. Listed as "healthy" on
    My Computer>> Manage >> Computer Management >> Disk Management
    Slave drive now has no file system listed, and size listed as 128 GB. BIOS setting LBA/Auto for all drives.

    Used diskmap:
    [DiskSize here incorrect; /d1 = Slave drive]

    C:\>diskmap /d1
    Cylinders HeadsPerCylinder SectorsPerHead BytesPerSector MediaType
    16709 255 63 512 12
    TrackSize = 32256, CylinderSize = 8225280, DiskSize = 137436203520 (131069MB)

    Signature = 0x00000001
    StartingOffset PartitionLength StartingSector PartitionNumber
    137438952960 0 1

    MBR:
    Starting Ending System Relative Total
    Cylinder Head Sector Cylinder Head Sector ID Sector Sectors
    0 0 52 1023 254 63 0x07 51 771987459
    1023 2 28 1023 223 27 0x07 771971598 102396168
    1023 223 28 1023 16 63 0x07 874367766 102401370
    0 0 0 0 0 0 0x00 0 0


    Concerned about Signature = 0x00000001, have always read of it been hex AA55
    Now the signature of an identical disk, with only one partition has a signature of
    => Signature = 0x32d28ddc ? now I am a tad bit confused. Could have changed it with a Hex Editor but now I am not sure what it should be changed to.



    Used MBRWizard:

    C:\>MBRWiz /Disk=1 /List

    Disk: 1 Size: 131G CHS: 16709 255 63
    Pos MBRndx Type/Name Size Active Hide Start Sector Sectors DL Vol Label
    --- ------ ---------- ---- ------ ---- ------------ ------------ -- ----------
    0 0 07-NTFS 377G No No 51 771,987,459 I: <None>
    1 1 07-NTFS 50G No No 771,971,598 102,396,168 -- <None>
    2 2 07-NTFS 50G No No 874,367,766 102,401,370 -- <None>


    Oddly enough volume type here is maintained as NTFS but not shown in Disk Management, probably because of disk size.

    Attempt at correcting the Labels failed
    [Error 106: - Unable to assign label to selected volume]

    Restoration of the MBR from a backup copy, showed "... MBR was successfully restored from ..." message but actually remained the same.

    Is this a MBR problem, the LBA / 137 Gb barrier or ?
    and how do I get around it without destroying the data on the disk?

    Thanks!
     
  2. Elvandil

    Elvandil

    Joined:
    Aug 1, 2003
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    51,988
    Have you reinstalled all Windows updates and service packs? This is probably a limitation of the NTFS driver.
     
  3. jaymax

    jaymax Thread Starter

    Joined:
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    Yes I updated to SP4, and did the Automatic Windows update. I thought about the NTFS drivers but other NTFS disks in the system seem fine.
     
  4. Elvandil

    Elvandil

    Joined:
    Aug 1, 2003
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    51,988
    If you think the only problem may be with the file system or partition itself and not with the system, then try restoring the partition table.

    Testdisk
    Testdisk Boot Floppy Image
    Testdisk on Live CD

    Does the BIOS see the correct drive size and is it set to automatic? Does the board support drives that size?
     
  5. jaymax

    jaymax Thread Starter

    Joined:
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    I looked into the use of Testdisks and did notice some anomalies but did not pursue it because I was not too familiar with the program.

    The question I have is, does Testdisk destroy the data while restoring the partitions?

    Couldn't find any substantive documentation on Testdisk

    Will post the output if I run into any roadblocks
     
  6. TheOutcaste

    TheOutcaste

    Joined:
    Aug 7, 2007
    Messages:
    9,028
    After re-installing Win2k, you need to enable 48-bit Logical Block Addressing in the registry to be able to see drives larger than 137 GB.

    See this article for the key to add (Edit: Value to add actually):
    48-Bit LBA Support for ATAPI Disk Drives in Windows 2000

    Enabling this might not restore the drive; the partition table may have been modified by Win2K. Once you've added the registry key and rebooted, if it still can't be seen, TestDisk should be able to restore the partition table. It's pretty safe to use, it only modifies the partition table, doesn't write to the data portion of the drive.

    The first link to TestDisk in Elvandil's post has quite a bit of documentation and examples, though a lot of it does assume some familiarity with technical concepts the average user doesn't normally have.

    Feel free to post screen shots or questions.

    HTH

    Jerry
     
  7. jaymax

    jaymax Thread Starter

    Joined:
    May 28, 2009
    Messages:
    31
    OK I goofed here, there is considerable documentation on a wiki page although much in other languages. However not much on partition restoration specifically but I'll figure it out.

    BTW: Thought that by running SP4 that it takes care of LBA issues, actually thought that SP3 & above handled that. Could not find LBA related subkeys referenced in the registry either.
     
  8. jaymax

    jaymax Thread Starter

    Joined:
    May 28, 2009
    Messages:
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    Hello Elvandil,
    The BIOS is set for LBA on all drives, other large drives are recognized. This disk was also recognized before the O/S system reinstallation on another disk. Doesn't SP3 and above take care of LBA issues? Went to KB on support.microsoft.com but did not find the LBA related subkey referenced there in my registry.
    ---------------
    Output from Testdisk run (indented):
    Select a media (use Arrow keys, then press Enter):
    Disk /dev/sda - 61 GB / 57 GiB - Maxtor 6Y060L0
    Disk /dev/sdb - 137 GB / 127 GiB - Maxtor 6H500R0 *
    Disk /dev/sdc - 320 GB / 298 GiB - SiI RAID 1 Set 0
    Disk /dev/sdd - 160 GB / 149 GiB - MAXTOR S TM3160812AS
    Disk /dev/sde - 160 GB / 149 GiB - MAXTOR S TM3160812AS
    Disk /dev/sdf - 400 GB / 372 GiB - ST340083 2A
    Disk /dev/sdg - 500 GB / 465 GiB - Maxtor 6 H500R0

    [Proceed ] [ Quit ]

    Note: Disk capacity must be correctly detected for a successful recovery.
    If a disk listed above has incorrect size, check HD jumper settings, BIOS
    detection, and install the latest OS patches and disk drivers.
    * Incorrect Disk Capacity here (Problem Disk)

    I have SP4 installed and all the hotfixes etc. which SP4 would have covered I think?
    ________________________________

    Then:
    Disk /dev/sdb - 137 GB / 127 GiB - CHS 16709 255 63

    The Harddisk size seems to be 137GB.
    Support for 48-bit Logical Block Addressing (LBA) is needed to access
    hard disks larger than 137 GB.
    Update Windows to support LBA48 (minimum: W2K SP4 or XP SP1)


    [ Continue ] The HD is really 137 GB only.
    [ Quit ] The HD is bigger, it's safer to enable LBA48 support first.
    HD is really 500 Gb ; 377 Gb; 50 Gb; and 50 Gb's Partitions respectively
    Already runniing W2K SP4
    ________________________________

    Then:
    Ignoring highlighted 'Quit' option & Continuing
    Disk /dev/sdb - 137 GB / 127 GiB - Maxtor 6H500R0 {Selected}

    Please select the partition table type, press Enter when done.
    [Intel ] Intel/PC partition {Selected}
    Selected types shown above from option list
    ________________________________

    Then:
    Analyse
    Disk /dev/sdb - 137 GB / 127 GiB - CHS 16709 255 63
    Current partition structure:
    Partition Start End Size in sectors

    Warning: Incorrect number of heads/cylinder 102 (NTFS) != 255 (HD)
    Warning: Incorrect number of sectors per track 51 (NTFS) != 63 (HD)
    1 P HPFS - NTFS 0 0 52 48053 254 63 771987459 [D2_V1]
    Invalid NTFS or EXFAT boot
    2 P HPFS - NTFS 48053 2 28 54426 223 27 102396168
    2 P HPFS - NTFS 48053 2 28 54426 223 27 102396168
    Invalid NTFS or EXFAT boot
    3 P HPFS - NTFS 54426 223 28 60801 16 63 102401370
    3 P HPFS - NTFS 54426 223 28 60801 16 63 102401370
    No partition is bootable
    Space conflict between the following two partitions
    1 P HPFS - NTFS 0 0 52 48053 254 63 771987459 [D2_V1]
    2 P HPFS - NTFS 48053 2 28 54426 223 27 102396168

    *=Primary bootable P=Primary L=Logical E=Extended D=Deleted
    Seems to identify the partitions and overlapping conflict of sectors
    And the disc is non-booting just for storage.
    ________________________________
    I went through the Quicksearch option to locate the partitions

    Then: ==>
    Disk /dev/sdb - 137 GB / 127 GiB - CHS 16709 255 63

    The harddisk (137 GB / 127 GiB) seems too small! (< 395 GB / 368 GiB)
    Check the harddisk size: HD jumpers settings, BIOS detection...

    The following partition can't be recovered:
    Partition Start End Size in sectors
    HPFS - NTFS 0 0 52 48053 2 27 771971547 [D2_V1]

    [ Continue ]
    NTFS, 395 GB / 368 GiB
    I am stuck by the apparent LBA SNAFU
    ________________________________

    Then:
    Continuing =>
    Disk /dev/sdb - 137 GB / 127 GiB - CHS 16709 255 63
    Partition Start End Size in sectors

    Structure: Ok.

    Keys A: add partition, L: load backup, Enter: to continue
    ________________________________

    Then:
    Continuing w/ Enter =>
    Disk /dev/sdb - 137 GB / 127 GiB - CHS 16709 255 63

    Partition Start End Size in sectors

    No partition found or selected for recovery

    [ Quit ] [Deeper Search]
    ________________________________

    Then: Selected Deeper Search
    Disk /dev/sdb - 137 GB / 127 GiB - CHS 16709 255 63

    The harddisk (137 GB / 127 GiB) seems too small! (< 395 GB / 368 GiB)
    Check the harddisk size: HD jumpers settings, BIOS detection...

    The following partition can't be recovered:
    Partition Start End Size in sectors
    HPFS - NTFS 0 0 52 48053 2 27 771971547 [D2_V1]


    [ Continue ]
    NTFS, 395 GB / 368 GiB
    ________________________________

    Then:
    Disk /dev/sdb - 137 GB / 127 GiB - CHS 16709 255 63
    Partition Start End Size in sectors
    L HPFS - NTFS 6791 1 1 10691 254 63 62669502


    Structure: Ok. Use Up/Down Arrow keys to select partition.
    Use Left/Right Arrow keys to CHANGE partition characteristics:
    *=Primary bootable P=Primary L=Logical E=Extended D=Deleted
    Keys A: add partition, L: load backup, T: change type, P: list files,
    Enter: to continue
    NTFS found using backup sector!, 32 GB / 29 GiB
    Other Partitions not found apparently? and the one listed is now L, which I can change. is highlighted green
    ________________________________

    If I Continue with 'Enter'
    Then: =>
    Disk /dev/sdb - 137 GB / 127 GiB - CHS 16709 255 63

    Partition Start End Size in sectors

    1 E extended LBA 6791 0 1 10691 254 63 62669565
    5 L HPFS - NTFS 6791 1 1 10691 254 63 62669502


    [ Quit ] [ Write ] [Extd Part]
    ________________________________

    Now at this point I Quit' and returned to main menu

    ________________________________

    MBR data saved earlier for this disk

    Pos MBRndx Type/Name Size Active Hide Start Sector Sectors
    --- ------ ---------- ---- ------ ---- ------------ ------------
    0 0 07-NTFS 377G No No 51 771,987,459
    1 1 07-NTFS 50G No No 771,971,598 102,396,168
    2 2 07-NTFS 50G No No 874,367,766 102,401,370


    Thanks, if you prefer screenshots, let me know
    I have done this low level formating with UNIX disks but not with data so I am a bit wary.
    Thanks again
     
  9. TheOutcaste

    TheOutcaste

    Joined:
    Aug 7, 2007
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    You'd think so, but according to the article, you have to edit/add the value:
    Did you add the EnableBigLba value?

    The Edit box to enter the value won't appear until you click OK on the Add Value dialog

    You can also do this in Regedit, except it's Edit | New | DWORD value. Or right click in right pane, New | DWORD Value.

    Once created and named, double click to set it to 1
     
  10. jaymax

    jaymax Thread Starter

    Joined:
    May 28, 2009
    Messages:
    31
    Hi Jerry,

    The HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Atapi\Parameters

    Does not exist in the registry, I'll go ahead an add it

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Atapi

    Does exist

    May I ask a question, then why does it handle the other large disks with no apparent problem?

    Thanks again
     

    Attached Files:

  11. TheOutcaste

    TheOutcaste

    Joined:
    Aug 7, 2007
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    9,028
    The Atapi folder is still showing a + sign, means there are folders under it. Double click to expand it, then I think you'll see the Parameters folder.

    I didn't even notice the sizes of the other disks. Don't have a good answer for why they are seen OK, unless none of them have partitions larger than 137 GB.
    Couple of other guesses:
    They all have more than one partition, and this problem disk only had one
    They weren't connected until after SP4 was installed.
    Not sure why these last two would make a difference, just guesses. I haven't run into this issue yet. Will be adding a 400 GB drive to a Win2k System next week so maybe I'll finally run into this. Currently have a 135 GiB (145 GB) RAID array on a Win2K SP2 system, but the RAID driver supplies the LBA support.
     
  12. jaymax

    jaymax Thread Starter

    Joined:
    May 28, 2009
    Messages:
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    Well, I'll be darned, it eventually opened up after doing a regedit. Anyway everything is working now. thanks again.
    Kind of odd one of the other disk was the same size 500Gb in one partition

    Anyway thanks again
     
  13. TheOutcaste

    TheOutcaste

    Joined:
    Aug 7, 2007
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    9,028
    Hey, what can I say, it's Windows.:rolleyes:

    If your issue has been resolved you (and ONLY you) can mark this thread Solved by using the Mark Solved button at the Top Left of this thread (above the first post) :)

    [​IMG]

    Jerry
     
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