Rebuild BS FAT16 - Can't find cluster size Topic is solved

[jeremyp52]

Hello,

Trying to restore Boot sector for hard drive pulled out of vintage 386 system.

Have consulted wiki for FAT boot sector repair - https://www.cgsecurity.org/wiki/Advanced_FAT_Repair

Began process, it identified the drive as FAT : 32 after doing a FAT table search, then began a subdirectory search, which ran all night. It informed me Can't find cluster size. Here is an example of what the main Boot menu looks like:

Disk \\.\PhysicalDrive1 - 2559 MB / 2441 MiB - CHS 311 255 63
Partition Start End Size in sectors
1 P FAT16 LBA 0 2 3 234 152 46 3768704

Boot sector
Bad

A valid FAT Boot sector must be present in order to access
any data; even if the partition is not bootable.

Here is an example of when it is searching for directories. Note how it identifies this as FAT : 32:

Disk \\.\PhysicalDrive1 - 2559 MB / 2441 MiB - CHS 311 255 63
Partition Start End Size in sectors
1 P FAT16 LBA 0 2 3 234 152 46 3768704

FAT : 32
Search subdirectory 1024/3768704 3

And, ultimately when it fails:

Can't find cluster size

Here is a copy of the log:

Code: Select all

Tue Jan 25 16:17:26 2022
Command line: TestDisk

TestDisk 7.2-WIP, Data Recovery Utility, September 2021
Christophe GRENIER <grenier@cgsecurity.org>
https://www.cgsecurity.org
OS: Windows 8 (9200)
Compiler: GCC 11.2, Cygwin 3001.4
ext2fs lib: 1.45.3, ntfs lib: 10:0:0, reiserfs lib: none, ewf lib: 20140608, curses lib: ncurses 6.1
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\PhysicalDrive0)=1024215482368
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\PhysicalDrive1)=2559836160
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\C:)=1004189761024
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\D:)=1929576448
Hard disk list
Disk \\.\PhysicalDrive0 - 1024 GB / 953 GiB - CHS 124520 255 63, sector size=512 - Intel Raid 0 Volume, S/N:ASUS_OS, FW:1.0.00
Disk \\.\PhysicalDrive1 - 2559 MB / 2441 MiB - CHS 311 255 63, sector size=512 - DW CCA23 05H0, S/N:20131013

Partition table type (auto): Intel
Disk \\.\PhysicalDrive1 - 2559 MB / 2441 MiB - DW CCA23 05H0
Partition table type: Intel

Interface Advanced
Geometry from i386 MBR: head=153 sector=46


test_FAT()
 1 P FAT16 LBA                0   2  3   234 152 46    3768704
sector_size  0
cluster_size 0
reserved     0
fats         0
dir_entries  0
sectors      0
media        00
fat_length   0
secs_track   0
heads        0
hidden       0
total_sect   0
check_part_i386 failed for partition type 0E
 1 P FAT16 LBA                0   2  3   234 152 46    3768704

fat1x_boot_sector
 1 P FAT16 LBA                0   2  3   234 152 46    3768704
Boot sector
Bad

A valid FAT Boot sector must be present in order to access
any data; even if the partition is not bootable.

 1 P FAT16 LBA                0   2  3   234 152 46    3768704
rebuild_FAT_BS p_fat12 0, p_fat16 1, p_fat32 1
fat_find_type(max_offset=29507, p_fat12=0, p_fat16=1, p_fat32=1, debug=1, dump_ind=0)
FAT16 at 5681(0/92/14), nbr=1
FAT32 at 11460(0/183/60), nbr=18
first_fat 11460, second_fat 5681
FAT : 32, reserved=0, fat_length=0
find_sectors_per_cluster skip_sectors=172 (skip_offset=88064)
sector 496, cluster 2
sector 688, cluster 5
sector 752, cluster 6
find_sectors_per_cluster_aux
sectors_per_cluster=64 offset=496 nbr=2 FAT : 16
Can't find cluster size

fat1x_boot_sector
 1 P FAT16 LBA                0   2  3   234 152 46    3768704
Boot sector
Bad

A valid FAT Boot sector must be present in order to access
any data; even if the partition is not bootable.

[recuperation]

If Testdisk fails to propose a valid boot sector you should contact a professional recovery company.
This is my advice because you are not talking about trying to perform data recovery but want to logically repair your drive.

[jeremyp52]

If Testdisk fails to propose a valid boot sector you should contact a professional recovery company.
This is my advice because you are not talking about trying to perform data recovery but want to logically repair your drive.

Thank you!