How to make a valid FAT Boot sector

Using TestDisk to repair the filesystem
Forum rules
When asking for technical support:
- Search for posts on the same topic before posting a new question.
- Give clear, specific information in the title of your post.
- Include as many details as you can, MOST POSTS WILL GET ONLY ONE OR TWO ANSWERS.
- Post a follow up with a "Thank you" or "This worked!"
- When you learn something, use that knowledge to HELP ANOTHER USER LATER.
Before posting, please read https://www.cgsecurity.org/testdisk.pdf
Locked
Message
Author
retrobob
Posts: 4
Joined: 07 Feb 2021, 02:51

How to make a valid FAT Boot sector

#1 Post by retrobob »

What is my next step?
Push me in the right direction

Mon Feb 8 13:52:13 2021
Command line: TestDisk

TestDisk 7.2-WIP, Data Recovery Utility, December 2020
Christophe GRENIER <grenier@cgsecurity.org>
https://www.cgsecurity.org
OS: Windows 7 (7601) SP1
Compiler: GCC 9.3, Cygwin32 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(/dev/sda)=2000398934016
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(/dev/sdb)=2000398933504
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(/dev/sdd)=255869321216
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\PhysicalDrive0)=2000398934016
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\PhysicalDrive1)=2000398933504
filewin32_getfilesize(\\.\PhysicalDrive2) GetFileSize err Incorrect function.

filewin32_setfilepointer(\\.\PhysicalDrive2) SetFilePointer err Incorrect function.

Warning: can't get size for \\.\PhysicalDrive2
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\PhysicalDrive3)=255869321216
filewin32_getfilesize(\\.\PhysicalDrive4) GetFileSize err Incorrect function.

filewin32_setfilepointer(\\.\PhysicalDrive4) SetFilePointer err Incorrect function.

Warning: can't get size for \\.\PhysicalDrive4
filewin32_getfilesize(\\.\PhysicalDrive5) GetFileSize err Incorrect function.

filewin32_setfilepointer(\\.\PhysicalDrive5) SetFilePointer err Incorrect function.

Warning: can't get size for \\.\PhysicalDrive5
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\C:)=2000291889152
filewin32_getfilesize(\\.\D:) GetFileSize err Incorrect function.

filewin32_setfilepointer(\\.\D:) SetFilePointer err Incorrect function.

Warning: can't get size for \\.\D:
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\E:)=2000395698176
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\F:)=0
Warning: can't get size for \\.\F:
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\G:)=0
Warning: can't get size for \\.\G:
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\H:)=0
Warning: can't get size for \\.\H:
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\I:)=44040192
Hard disk list
Disk /dev/sda - 2000 GB / 1863 GiB - CHS 243201 255 63, sector size=512 - ST2000DM008-2FR102, S/N:202020202020202020202020465a324c46455456, FW:0001
Disk /dev/sdb - 2000 GB / 1863 GiB - CHS 243201 255 63, sector size=512 - Seagate BUP Slim BL, S/N:NA9LWKJ4, FW:0108
Disk /dev/sdd - 255 GB / 238 GiB - CHS 31107 255 63, sector size=512 - Generic- USB3.0 CRW -1, FW:1.00

Partition table type (auto): Intel
Disk /dev/sdd - 255 GB / 238 GiB - Generic- USB3.0 CRW -1
Partition table type: Intel

Analyse Disk /dev/sdd - 255 GB / 238 GiB - CHS 31107 255 63
Geometry from i386 MBR: head=255 sector=63
FAT32 at 0/130/3
Info: size boot_sector 85611, partition 86016
FAT1 : 32-690
FAT2 : 691-1349
start_rootdir : 1350 root cluster : 2
Data : 1350-85610
sectors : 85611
cluster_size : 1
no_of_cluster : 84261 (2 - 84262)
fat_length 659 calculated 659
heads/cylinder 64 (FAT) != 255 (HD)
sect/track 32 (FAT) != 63 (HD)
Current partition structure:
Warning: number of heads/cylinder mismatches 64 (FAT) != 255 (HD)
Warning: number of sectors per track mismatches 32 (FAT) != 63 (HD)
1 * FAT32 0 130 3 5 220 23 86016 [boot]
2 P Linux 6 30 25 31107 171 40 499646464 [rootfs]

search_part()
Disk /dev/sdd - 255 GB / 238 GiB - CHS 31107 255 63
FAT32 at 0/130/3
FAT1 : 32-690
FAT2 : 691-1349
start_rootdir : 1350 root cluster : 2
Data : 1350-85610
sectors : 85611
cluster_size : 1
no_of_cluster : 84261 (2 - 84262)
fat_length 659 calculated 659
heads/cylinder 64 (FAT) != 255 (HD)
sect/track 32 (FAT) != 63 (HD)

FAT32 at 0/130/3
FAT: cluster=2(0x2), pos=9542
FAT: cluster=107(0x6b), pos=9647
FAT: cluster=273(0x111), pos=9813
FAT: cluster=471(0x1d7), pos=10011
FAT: cluster=42904(0xa798), pos=52444
FAT: cluster=2885(0xb45), pos=12425
FAT: cluster=5728(0x1660), pos=15268
FAT32 0 130 3 5 213 59 85611 [boot]
FAT32, blocksize=512, 43 MB / 41 MiB

recover_EXT2: s_block_group_nr=0/1906, s_mnt_count=26/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8096
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 62455808
recover_EXT2: part_size 499646464
Filesystem created: Tue Mar 13 18:10:46 2018
Last mount time: Mon Nov 25 10:29:01 2019
Linux 6 30 25 31107 171 40 499646464 [rootfs]
ext4 blocksize=4096 Large_file Sparse_SB, 255 GB / 238 GiB
file_pread(6,8,buffer,499744768(31107/171/41)) ReadFile The drive cannot find the sector requested.

file_pread(6,1,buffer,499744768(31107/171/41)) ReadFile The drive cannot find the sector requested.

file_pread(6,1,buffer,499744769(31107/171/42)) lseek err Invalid argument
file_pread(6,14,buffer,499744770(31107/171/43)) lseek err Invalid argument
file_pread(6,3,buffer,499744784(31107/171/57)) lseek err Invalid argument
file_pread(6,3,buffer,499744831(31107/172/41)) lseek err Invalid argument
file_pread(6,8,buffer,499744847(31107/172/57)) lseek err Invalid argument
file_pread(6,11,buffer,499744894(31107/173/41)) lseek err Invalid argument
file_pread(6,2,buffer,499746816(31107/204/10)) lseek err Invalid argument

Results
* FAT32 0 130 3 5 220 23 86016 [boot]
FAT32, blocksize=512, 44 MB / 42 MiB
P Linux 6 30 25 31107 171 40 499646464 [rootfs]
ext4 blocksize=4096 Large_file Sparse_SB, 255 GB / 238 GiB

interface_write()
1 * FAT32 0 130 3 5 220 23 86016 [boot]
2 P Linux 6 30 25 31107 171 40 499646464 [rootfs]
simulate write!

write_mbr_i386: starting...
write_all_log_i386: starting...
No extended partition

Interface Advanced
Geometry from i386 MBR: head=255 sector=63
FAT32 at 0/130/3
Info: size boot_sector 85611, partition 86016
FAT1 : 32-690
FAT2 : 691-1349
start_rootdir : 1350 root cluster : 2
Data : 1350-85610
sectors : 85611
cluster_size : 1
no_of_cluster : 84261 (2 - 84262)
fat_length 659 calculated 659
heads/cylinder 64 (FAT) != 255 (HD)
sect/track 32 (FAT) != 63 (HD)
1 * FAT32 0 130 3 5 220 23 86016 [boot]
FAT32, blocksize=512, 44 MB / 42 MiB
2 P Linux 6 30 25 31107 171 40 499646464 [rootfs]
ext4 blocksize=4096 Large_file Sparse_SB, 255 GB / 238 GiB

fat32_boot_sector
1 * FAT32 0 130 3 5 220 23 86016 [boot]
FAT32, blocksize=512, 44 MB / 42 MiB
FAT32 at 0/130/3
Info: size boot_sector 85611, partition 86016
FAT1 : 32-690
FAT2 : 691-1349
start_rootdir : 1350 root cluster : 2
Data : 1350-85610
sectors : 85611
cluster_size : 1
no_of_cluster : 84261 (2 - 84262)
fat_length 659 calculated 659
heads/cylinder 64 (FAT) != 255 (HD)
sect/track 32 (FAT) != 63 (HD)
FAT32 at 0/130/3
Info: size boot_sector 85611, partition 86016
FAT1 : 32-690
FAT2 : 691-1349
start_rootdir : 1350 root cluster : 2
Data : 1350-85610
sectors : 85611
cluster_size : 1
no_of_cluster : 84261 (2 - 84262)
fat_length 659 calculated 659
heads/cylinder 64 (FAT) != 255 (HD)
sect/track 32 (FAT) != 63 (HD)
Boot sector
Warning: number of heads/cylinder mismatches 64 (FAT) != 255 (HD)
Warning: number of sectors per track mismatches 32 (FAT) != 63 (HD)
OK

Backup boot sector
Warning: number of heads/cylinder mismatches 64 (FAT) != 255 (HD)
Warning: number of sectors per track mismatches 32 (FAT) != 63 (HD)
OK

Second sectors (cluster information) are not identical.

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

recuperation
Posts: 2718
Joined: 04 Jan 2019, 09:48
Location: Hannover, Deutschland (Germany, Allemagne)

Re: How to make a valid FAT Boot sector

#2 Post by recuperation »

Testdisk can't do anything for you here. You would need to compare both boot sectors to each other, compare that to the content you find at the designated locations and adjusted both sectors accordingly to the most probable figures.

Otherwise try Photorec or any other recovery software.

retrobob
Posts: 4
Joined: 07 Feb 2021, 02:51

Re: How to make a valid FAT Boot sector

#3 Post by retrobob »

recommended disk editor to compare both boot sectors to each other?

recuperation
Posts: 2718
Joined: 04 Jan 2019, 09:48
Location: Hannover, Deutschland (Germany, Allemagne)

Re: How to make a valid FAT Boot sector

#4 Post by recuperation »

No recommendation. Every editor will do. If it hangs you know it wants do load the whole file into memory.

retrobob
Posts: 4
Joined: 07 Feb 2021, 02:51

Re: How to make a valid FAT Boot sector

#5 Post by retrobob »

Trying to do a ADVANCED FAT REPAIR

Please look over my testdisk.log and give further advice

Thu Feb 25 11:18:47 2021
Command line: TestDisk

TestDisk 7.2-WIP, Data Recovery Utility, December 2020
Christophe GRENIER <grenier@cgsecurity.org>
https://www.cgsecurity.org
OS: Windows 7 (7601) SP1
Compiler: GCC 9.3, Cygwin32 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(/dev/sda)=2000398934016
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(/dev/sdb)=2000398933504
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(/dev/sdd)=255869321216
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\PhysicalDrive0)=2000398934016
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\PhysicalDrive1)=2000398933504
filewin32_getfilesize(\\.\PhysicalDrive2) GetFileSize err Incorrect function.

filewin32_setfilepointer(\\.\PhysicalDrive2) SetFilePointer err Incorrect function.

Warning: can't get size for \\.\PhysicalDrive2
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\PhysicalDrive3)=255869321216
filewin32_getfilesize(\\.\PhysicalDrive4) GetFileSize err Incorrect function.

filewin32_setfilepointer(\\.\PhysicalDrive4) SetFilePointer err Incorrect function.

Warning: can't get size for \\.\PhysicalDrive4
filewin32_getfilesize(\\.\PhysicalDrive5) GetFileSize err Incorrect function.

filewin32_setfilepointer(\\.\PhysicalDrive5) SetFilePointer err Incorrect function.

Warning: can't get size for \\.\PhysicalDrive5
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\C:)=2000291889152
filewin32_getfilesize(\\.\D:) GetFileSize err Incorrect function.

filewin32_setfilepointer(\\.\D:) SetFilePointer err Incorrect function.

Warning: can't get size for \\.\D:
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\E:)=2000395698176
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\F:)=0
Warning: can't get size for \\.\F:
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\G:)=0
Warning: can't get size for \\.\G:
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\H:)=0
Warning: can't get size for \\.\H:
disk_get_size_win32 IOCTL_DISK_GET_LENGTH_INFO(\\.\I:)=44040192
Hard disk list
Disk /dev/sda - 2000 GB / 1863 GiB - CHS 243201 255 63, sector size=512 - ST2000DM008-2FR102, S/N:202020202020202020202020465a324c46455456, FW:0001
Disk /dev/sdb - 2000 GB / 1863 GiB - CHS 243201 255 63, sector size=512 - Seagate BUP Slim BL, S/N:NA9LWKJ4, FW:0108
Disk /dev/sdd - 255 GB / 238 GiB - CHS 31107 255 63, sector size=512 - Generic- USB3.0 CRW -1, FW:1.00

Partition table type (auto): Intel
Disk /dev/sdd - 255 GB / 238 GiB - Generic- USB3.0 CRW -1
Partition table type: Intel

Interface Advanced
Geometry from i386 MBR: head=255 sector=63
FAT32 at 0/130/3
Info: size boot_sector 85611, partition 86016
FAT1 : 32-690
FAT2 : 691-1349
start_rootdir : 1350 root cluster : 2
Data : 1350-85610
sectors : 85611
cluster_size : 1
no_of_cluster : 84261 (2 - 84262)
fat_length 659 calculated 659
heads/cylinder 64 (FAT) != 255 (HD)
sect/track 32 (FAT) != 63 (HD)
1 * FAT32 0 130 3 5 220 23 86016 [boot]
FAT32, blocksize=512, 44 MB / 42 MiB
2 P Linux 6 30 25 31107 171 40 499646464 [rootfs]
ext4 blocksize=4096 Large_file Sparse_SB, 255 GB / 238 GiB

fat32_boot_sector
1 * FAT32 0 130 3 5 220 23 86016 [boot]
FAT32, blocksize=512, 44 MB / 42 MiB
FAT32 at 0/130/3
Info: size boot_sector 85611, partition 86016
FAT1 : 32-690
FAT2 : 691-1349
start_rootdir : 1350 root cluster : 2
Data : 1350-85610
sectors : 85611
cluster_size : 1
no_of_cluster : 84261 (2 - 84262)
fat_length 659 calculated 659
heads/cylinder 64 (FAT) != 255 (HD)
sect/track 32 (FAT) != 63 (HD)
FAT32 at 0/130/3
Info: size boot_sector 85611, partition 86016
FAT1 : 32-690
FAT2 : 691-1349
start_rootdir : 1350 root cluster : 2
Data : 1350-85610
sectors : 85611
cluster_size : 1
no_of_cluster : 84261 (2 - 84262)
fat_length 659 calculated 659
heads/cylinder 64 (FAT) != 255 (HD)
sect/track 32 (FAT) != 63 (HD)
Boot sector
Warning: number of heads/cylinder mismatches 64 (FAT) != 255 (HD)
Warning: number of sectors per track mismatches 32 (FAT) != 63 (HD)
OK

Backup boot sector
Warning: number of heads/cylinder mismatches 64 (FAT) != 255 (HD)
Warning: number of sectors per track mismatches 32 (FAT) != 63 (HD)
OK

Second sectors (cluster information) are not identical.

A valid FAT Boot sector must be present in order to access
any data; even if the partition is not bootable.
Boot sector Backup boot sector
0000 eb58906d 6b66732e .X.mkfs. eb58906d 6b66732e .X.mkfs.
0008 66617400 02012000 fat... . 66617400 02012000 fat... .
0010 02000000 00f80000 ........ 02000000 00f80000 ........
0018 20004000 00000000 .@..... 20004000 00000000 .@.....
0020 6b4e0100 93020000 kN...... 6b4e0100 93020000 kN......
0028 00000000 02000000 ........ 00000000 02000000 ........
0030 01000600 00000000 ........ 01000600 00000000 ........
0038 00000000 00000000 ........ 00000000 00000000 ........
0040 80002979 dc5ba762 ..)y.[.b 80002979 dc5ba762 ..)y.[.b
0048 6f6f7420 20202020 oot 6f6f7420 20202020 oot
0050 20204641 54333220 FAT32 20204641 54333220 FAT32
0058 20200e1f be777cac ...w|. 20200e1f be777cac ...w|.
0060 22c0740b 56b40ebb ".t.V... 22c0740b 56b40ebb ".t.V...
0068 0700cd10 5eebf032 ....^..2 0700cd10 5eebf032 ....^..2
0070 e4cd16cd 19ebfe54 .......T e4cd16cd 19ebfe54 .......T
0078 68697320 6973206e his is n 68697320 6973206e his is n
0080 6f742061 20626f6f ot a boo 6f742061 20626f6f ot a boo
0088 7461626c 65206469 table di 7461626c 65206469 table di
0090 736b2e20 20506c65 sk. Ple 736b2e20 20506c65 sk. Ple
0098 61736520 696e7365 ase inse 61736520 696e7365 ase inse
00A0 72742061 20626f6f rt a boo 72742061 20626f6f rt a boo
00A8 7461626c 6520666c table fl 7461626c 6520666c table fl
00B0 6f707079 20616e64 oppy and 6f707079 20616e64 oppy and
00B8 0d0a7072 65737320 ..press 0d0a7072 65737320 ..press
00C0 616e7920 6b657920 any key 616e7920 6b657920 any key
00C8 746f2074 72792061 to try a 746f2074 72792061 to try a
00D0 6761696e 202e2e2e gain ... 6761696e 202e2e2e gain ...
00D8 200d0a00 00000000 ....... 200d0a00 00000000 .......
00E0 00000000 00000000 ........ 00000000 00000000 ........
00E8 00000000 00000000 ........ 00000000 00000000 ........
00F0 00000000 00000000 ........ 00000000 00000000 ........
00F8 00000000 00000000 ........ 00000000 00000000 ........
0100 00000000 00000000 ........ 00000000 00000000 ........
0108 00000000 00000000 ........ 00000000 00000000 ........
0110 00000000 00000000 ........ 00000000 00000000 ........
0118 00000000 00000000 ........ 00000000 00000000 ........
0120 00000000 00000000 ........ 00000000 00000000 ........
0128 00000000 00000000 ........ 00000000 00000000 ........
0130 00000000 00000000 ........ 00000000 00000000 ........
0138 00000000 00000000 ........ 00000000 00000000 ........
0140 00000000 00000000 ........ 00000000 00000000 ........
0148 00000000 00000000 ........ 00000000 00000000 ........
0150 00000000 00000000 ........ 00000000 00000000 ........
0158 00000000 00000000 ........ 00000000 00000000 ........
0160 00000000 00000000 ........ 00000000 00000000 ........
0168 00000000 00000000 ........ 00000000 00000000 ........
0170 00000000 00000000 ........ 00000000 00000000 ........
0178 00000000 00000000 ........ 00000000 00000000 ........
0180 00000000 00000000 ........ 00000000 00000000 ........
0188 00000000 00000000 ........ 00000000 00000000 ........
0190 00000000 00000000 ........ 00000000 00000000 ........
0198 00000000 00000000 ........ 00000000 00000000 ........
01A0 00000000 00000000 ........ 00000000 00000000 ........
01A8 00000000 00000000 ........ 00000000 00000000 ........
01B0 00000000 00000000 ........ 00000000 00000000 ........
01B8 00000000 00000000 ........ 00000000 00000000 ........
01C0 00000000 00000000 ........ 00000000 00000000 ........
01C8 00000000 00000000 ........ 00000000 00000000 ........
01D0 00000000 00000000 ........ 00000000 00000000 ........
01D8 00000000 00000000 ........ 00000000 00000000 ........
01E0 00000000 00000000 ........ 00000000 00000000 ........
01E8 00000000 00000000 ........ 00000000 00000000 ........
01F0 00000000 00000000 ........ 00000000 00000000 ........
01F8 00000000 000055aa ......U. 00000000 000055aa ......U.
0200 52526141 00000000 RRaA.... 00000000 00000000 ........
0208 00000000 00000000 ........ 00000000 00000000 ........
0210 00000000 00000000 ........ 00000000 00000000 ........
0218 00000000 00000000 ........ 00000000 00000000 ........
0220 00000000 00000000 ........ 00000000 00000000 ........
0228 00000000 00000000 ........ 00000000 00000000 ........
0230 00000000 00000000 ........ 00000000 00000000 ........
0238 00000000 00000000 ........ 00000000 00000000 ........
0240 00000000 00000000 ........ 00000000 00000000 ........
0248 00000000 00000000 ........ 00000000 00000000 ........
0250 00000000 00000000 ........ 00000000 00000000 ........
0258 00000000 00000000 ........ 00000000 00000000 ........
0260 00000000 00000000 ........ 00000000 00000000 ........
0268 00000000 00000000 ........ 00000000 00000000 ........
0270 00000000 00000000 ........ 00000000 00000000 ........
0278 00000000 00000000 ........ 00000000 00000000 ........
0280 00000000 00000000 ........ 00000000 00000000 ........
0288 00000000 00000000 ........ 00000000 00000000 ........
0290 00000000 00000000 ........ 00000000 00000000 ........
0298 00000000 00000000 ........ 00000000 00000000 ........
02A0 00000000 00000000 ........ 00000000 00000000 ........
02A8 00000000 00000000 ........ 00000000 00000000 ........
02B0 00000000 00000000 ........ 00000000 00000000 ........
02B8 00000000 00000000 ........ 00000000 00000000 ........
02C0 00000000 00000000 ........ 00000000 00000000 ........
02C8 00000000 00000000 ........ 00000000 00000000 ........
02D0 00000000 00000000 ........ 00000000 00000000 ........
02D8 00000000 00000000 ........ 00000000 00000000 ........
02E0 00000000 00000000 ........ 00000000 00000000 ........
02E8 00000000 00000000 ........ 00000000 00000000 ........
02F0 00000000 00000000 ........ 00000000 00000000 ........
02F8 00000000 00000000 ........ 00000000 00000000 ........
0300 00000000 00000000 ........ 00000000 00000000 ........
0308 00000000 00000000 ........ 00000000 00000000 ........
0310 00000000 00000000 ........ 00000000 00000000 ........
0318 00000000 00000000 ........ 00000000 00000000 ........
0320 00000000 00000000 ........ 00000000 00000000 ........
0328 00000000 00000000 ........ 00000000 00000000 ........
0330 00000000 00000000 ........ 00000000 00000000 ........
0338 00000000 00000000 ........ 00000000 00000000 ........
0340 00000000 00000000 ........ 00000000 00000000 ........
0348 00000000 00000000 ........ 00000000 00000000 ........
0350 00000000 00000000 ........ 00000000 00000000 ........
0358 00000000 00000000 ........ 00000000 00000000 ........
0360 00000000 00000000 ........ 00000000 00000000 ........
0368 00000000 00000000 ........ 00000000 00000000 ........
0370 00000000 00000000 ........ 00000000 00000000 ........
0378 00000000 00000000 ........ 00000000 00000000 ........
0380 00000000 00000000 ........ 00000000 00000000 ........
0388 00000000 00000000 ........ 00000000 00000000 ........
0390 00000000 00000000 ........ 00000000 00000000 ........
0398 00000000 00000000 ........ 00000000 00000000 ........
03A0 00000000 00000000 ........ 00000000 00000000 ........
03A8 00000000 00000000 ........ 00000000 00000000 ........
03B0 00000000 00000000 ........ 00000000 00000000 ........
03B8 00000000 00000000 ........ 00000000 00000000 ........
03C0 00000000 00000000 ........ 00000000 00000000 ........
03C8 00000000 00000000 ........ 00000000 00000000 ........
03D0 00000000 00000000 ........ 00000000 00000000 ........
03D8 00000000 00000000 ........ 00000000 00000000 ........
03E0 00000000 72724161 ....rrAa 00000000 00000000 ........
03E8 ec9c0000 c6cb0000 ........ 00000000 00000000 ........
03F0 00000000 00000000 ........ 00000000 00000000 ........
03F8 00000000 000055aa ......U. 00000000 00000000 ........
0400 00000000 00000000 ........ 00000000 00000000 ........
0408 00000000 00000000 ........ 00000000 00000000 ........
0410 00000000 00000000 ........ 00000000 00000000 ........
0418 00000000 00000000 ........ 00000000 00000000 ........
0420 00000000 00000000 ........ 00000000 00000000 ........
0428 00000000 00000000 ........ 00000000 00000000 ........
0430 00000000 00000000 ........ 00000000 00000000 ........
0438 00000000 00000000 ........ 00000000 00000000 ........
0440 00000000 00000000 ........ 00000000 00000000 ........
0448 00000000 00000000 ........ 00000000 00000000 ........
0450 00000000 00000000 ........ 00000000 00000000 ........
0458 00000000 00000000 ........ 00000000 00000000 ........
0460 00000000 00000000 ........ 00000000 00000000 ........
0468 00000000 00000000 ........ 00000000 00000000 ........
0470 00000000 00000000 ........ 00000000 00000000 ........
0478 00000000 00000000 ........ 00000000 00000000 ........
0480 00000000 00000000 ........ 00000000 00000000 ........
0488 00000000 00000000 ........ 00000000 00000000 ........
0490 00000000 00000000 ........ 00000000 00000000 ........
0498 00000000 00000000 ........ 00000000 00000000 ........
04A0 00000000 00000000 ........ 00000000 00000000 ........
04A8 00000000 00000000 ........ 00000000 00000000 ........
04B0 00000000 00000000 ........ 00000000 00000000 ........
04B8 00000000 00000000 ........ 00000000 00000000 ........
04C0 00000000 00000000 ........ 00000000 00000000 ........
04C8 00000000 00000000 ........ 00000000 00000000 ........
04D0 00000000 00000000 ........ 00000000 00000000 ........
04D8 00000000 00000000 ........ 00000000 00000000 ........
04E0 00000000 00000000 ........ 00000000 00000000 ........
04E8 00000000 00000000 ........ 00000000 00000000 ........
04F0 00000000 00000000 ........ 00000000 00000000 ........
04F8 00000000 00000000 ........ 00000000 00000000 ........
0500 00000000 00000000 ........ 00000000 00000000 ........
0508 00000000 00000000 ........ 00000000 00000000 ........
0510 00000000 00000000 ........ 00000000 00000000 ........
0518 00000000 00000000 ........ 00000000 00000000 ........
0520 00000000 00000000 ........ 00000000 00000000 ........
0528 00000000 00000000 ........ 00000000 00000000 ........
0530 00000000 00000000 ........ 00000000 00000000 ........
0538 00000000 00000000 ........ 00000000 00000000 ........
0540 00000000 00000000 ........ 00000000 00000000 ........
0548 00000000 00000000 ........ 00000000 00000000 ........
0550 00000000 00000000 ........ 00000000 00000000 ........
0558 00000000 00000000 ........ 00000000 00000000 ........
0560 00000000 00000000 ........ 00000000 00000000 ........
0568 00000000 00000000 ........ 00000000 00000000 ........
0570 00000000 00000000 ........ 00000000 00000000 ........
0578 00000000 00000000 ........ 00000000 00000000 ........
0580 00000000 00000000 ........ 00000000 00000000 ........
0588 00000000 00000000 ........ 00000000 00000000 ........
0590 00000000 00000000 ........ 00000000 00000000 ........
0598 00000000 00000000 ........ 00000000 00000000 ........
05A0 00000000 00000000 ........ 00000000 00000000 ........
05A8 00000000 00000000 ........ 00000000 00000000 ........
05B0 00000000 00000000 ........ 00000000 00000000 ........
05B8 00000000 00000000 ........ 00000000 00000000 ........
05C0 00000000 00000000 ........ 00000000 00000000 ........
05C8 00000000 00000000 ........ 00000000 00000000 ........
05D0 00000000 00000000 ........ 00000000 00000000 ........
05D8 00000000 00000000 ........ 00000000 00000000 ........
05E0 00000000 00000000 ........ 00000000 00000000 ........
05E8 00000000 00000000 ........ 00000000 00000000 ........
05F0 00000000 00000000 ........ 00000000 00000000 ........
05F8 00000000 00000000 ........ 00000000 00000000 ........

FAT32
sector_size 512 512
cluster_size 1 1
reserved 32 32
fats 2 2
dir_entries 0 0
sectors 0 0
media F8 F8
fat_length 0 0
secs_track 32 32
heads 64 64
hidden 0 0
total_sect 85611 85611
fat32_length 659 659
flags 0000 0000
version 0.0 0.0
root_cluster 2 2
info_sector 1 1
backup_boot 6 6
free_count 40172 0
next_free 52166 0

fat32_boot_sector
1 * FAT32 0 130 3 5 220 23 86016 [boot]
FAT32, blocksize=512, 44 MB / 42 MiB
FAT32 at 0/130/3
Info: size boot_sector 85611, partition 86016
FAT1 : 32-690
FAT2 : 691-1349
start_rootdir : 1350 root cluster : 2
Data : 1350-85610
sectors : 85611
cluster_size : 1
no_of_cluster : 84261 (2 - 84262)
fat_length 659 calculated 659
heads/cylinder 64 (FAT) != 255 (HD)
sect/track 32 (FAT) != 63 (HD)
FAT32 at 0/130/3
Info: size boot_sector 85611, partition 86016
FAT1 : 32-690
FAT2 : 691-1349
start_rootdir : 1350 root cluster : 2
Data : 1350-85610
sectors : 85611
cluster_size : 1
no_of_cluster : 84261 (2 - 84262)
fat_length 659 calculated 659
heads/cylinder 64 (FAT) != 255 (HD)
sect/track 32 (FAT) != 63 (HD)
Boot sector
Warning: number of heads/cylinder mismatches 64 (FAT) != 255 (HD)
Warning: number of sectors per track mismatches 32 (FAT) != 63 (HD)
OK

Backup boot sector
Warning: number of heads/cylinder mismatches 64 (FAT) != 255 (HD)
Warning: number of sectors per track mismatches 32 (FAT) != 63 (HD)
OK

Second sectors (cluster information) are not identical.

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

recuperation
Posts: 2718
Joined: 04 Jan 2019, 09:48
Location: Hannover, Deutschland (Germany, Allemagne)

Re: How to make a valid FAT Boot sector

#6 Post by recuperation »

I can't help you any further.
If you want to play around, get yourself a small and fast USB stick, delete it completely, (partition) and format it, put some files on it and deletes crucial sectors on purpose. Then you can try to figure out what to do.

Locked