bad boot and backup boot sector - sector mismatch

Using TestDisk to repair the filesystem
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Krikke
Posts: 1
Joined: 22 Jan 2023, 16:04

bad boot and backup boot sector - sector mismatch

#1 Post by Krikke »

I have been working with testdisk (windows-version) to recover data from a 3tb hard disk of Western Digital with one NTFS partition.
Testdisk finds all files and enables me to copy them. I have recovered what is essential to me, but it would be nice if I could also keep the rest (old photos). However, my current set-up does not allow me to copy all of it, so I was looking into repairing the filesystem.

By using the step-by-step guide and the manual of Testdisk, I have found that both the boot sector and the backup boot sector are bad + the number of bytes per sector mismatches. I am avoiding to change the geometry of the disk, because I am afraid I would not be able to change it back and lose all the files.

Could anyone confirm if you can undo changing the geometry of a disk?
Do I have any other options?

Disk /dev/sdc - 3000 GB / 2794 GiB - CHS 364797 255 63
Current partition structure:
Partition Start End Size in sectors Warning: number of bytes per sector mismatches 4096 (NTFS) != 512 (HD)
Error: size boot_sector 732558080 > partition 4294967295
Invalid NTFS or exFAT boot
1 * HPFS - NTFS 0 32 33 267349 121 35 4294967295
1 * HPFS - NTFS 0 32 33 267349 121 35 4294967295

I can list all files (and copy them) through a quick search.
However, rebuilding the boot sector does not work. When I request a list of my files, it says 'Can't open filesystem. Filesystem seems damaged.'

Disk /dev/sdc - 3000 GB / 2794 GiB - CHS 364797 255 63
Partition Start End Size in sectors
1 * HPFS - NTFS 0 32 33 267349 121 35 4294967295 Boot sector
Warning: number of bytes per sector mismatches 4096 (NTFS) != 512 (HD)
Error: size boot_sector 732558080 > partition 4294967295
Status: Bad Backup boot sector
Status: Bad Sectors are not identical. A valid NTFS Boot sector must be present in order to access
any data; even if the partition is not bootable.

When looking into this post: https://www.cgsecurity.org/wiki/Advance ... MFT_Repair, I though repairing the MFT would be the next step, but there is no such option in (my version of) Testdisk.

All tips are welcome, thank you!

recuperation
Posts: 2303
Joined: 04 Jan 2019, 09:48
Location: Hannover, Deutschland (Germany, Allemagne)

Re: bad boot and backup boot sector - sector mismatch

#2 Post by recuperation »

Krikke wrote: 22 Jan 2023, 16:44 I have been working with testdisk (windows-version) to recover data from a 3tb hard disk of Western Digital with one NTFS partition.
Testdisk finds all files and enables me to copy them. I have recovered what is essential to me, but it would be nice if I could also keep the rest (old photos). However, my current set-up
Buy storage! Period.
does not allow me to copy all of it, so I was looking into repairing the filesystem.

By using the step-by-step guide and the manual of Testdisk, I have found that both the boot sector and the backup boot sector are bad + the number of bytes per sector mismatches.
Did you remove a hard disk from the external housing it came with?
I am avoiding to change the geometry of the disk,
You can't change the geometry of the disk - except where some interface electronics in an external housing is manipulating the sector size.
because I am afraid I would not be able to change it back and lose all the files.
Based on your current knowledge it is not a wise idea trying to "repair" your disk. The fact that you are lacking storage for a backup is already an important ingredient for an upcoming disaster.

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