MBR / bootsector / FAT wiped by FDISK - unreadable ! FINDPART (Mikkelsen)


P

p-k

To Hard Disk Experts
I have accidentally deleted, then reset, my partition with FDISK .

It is my main hard disk, so now I cannot use my system (except to boot
from floppy)

The disk is 3090 MB & 785 Cyl / 128 Hd / 63 Sect

The disk is now (according to dos) partitioned with one primary active
partition, but has not been formatted. (The original partition was also
a single, primary, fat32) Thus DOS does assign the disk the letter C,
but says "invalid media type" if it is accessed from the prompt.

I am sure most of my data is still on the disk but I cannot read any of
it until I can get the partition table & FAT (file llocation table)
information back. I may also need to write a new mbr, but I don't know.

I think a copy of a standard MBR & bootsector, needs to be copied to
the first few sectors of the disk, to make it readable again.

I don't really know how to do this.

I used a good program by Svend Olaf Mikkelsen - FINDPART - to get a
report (below)

Could anybody tell me if there is any chance of recovering the files on
the hard disk and, if so, how can it be done?


Findpart, version 4.42.
Copyright Svend Olaf Mikkelsen, 1999-2004.

OS: DOS 7.10

Disk: 1 Cylinders: 785 Heads: 128 Sectors: 63 MB: 3091

-PCyl N ID -----Rel -----Num ---MB -Start CHS- --End CHS-- BS CHS
Fdisk F6 sector 0 2 1
Fdisk F6 sector 1 0 1
Fdisk F6 sector 1 1 1
Fdisk F6 sector 2 0 1
Fdisk F6 sector 2 1 1
Fdisk F6 sector 3 0 1
Fdisk F6 sector 3 1 1
0 - 04 3741696 16128 7 464 0 1 465 127 63 B OK
Fdisk F6 sector 586 0 1
Fdisk F6 sector 586 1 1
Fdisk F6 sector 611 0 1
Fdisk F6 sector 611 1 1
0 - 07 63 6330177 3090 0 1 1 784 127 63 BU OK

-----FAT CHS -Size Cl --Root -Good -Rep. Maybe --Bad YYMMDD DataMB
0 1 33 6168 4# 2# 5874 196 0 98 040117 2409
464 0 2 32 1 512 32 0 0 0 040706 2
464 0 34 Second FAT not found.

Partitions according to partition tables on first harddisk:

-PCyl N ID -----Rel -----Num ---MB -Start CHS- --End CHS-- BS CHS
0 1*0C 63 6330177 3090 0 1 1 784 127 63 NB OK




I would be grateful for any help
Kind regards
Peter Khan
(the listed email address is invalid)
 
Ad

Advertisements

W

William the Wombat

To Hard Disk Experts
I have accidentally deleted, then reset, my partition with FDISK .


Acronis Recovery Expert might be worth a look at. I've found it easy and
effective at recovering lost partitions.
 
Z

Zvi Netiv

To Hard Disk Experts
I have accidentally deleted, then reset, my partition with FDISK .

Having deleted a partition by mistake is human. Resetting it with FDISK was a
mistake as it cleared the boot sector and maybe the FAT too!
It is my main hard disk, so now I cannot use my system (except to boot
from floppy)

The disk is 3090 MB & 785 Cyl / 128 Hd / 63 Sect

The disk is now (according to dos) partitioned with one primary active
partition, but has not been formatted. (The original partition was also
a single, primary, fat32) Thus DOS does assign the disk the letter C,
but says "invalid media type" if it is accessed from the prompt.

The "invalid media type" message indicates that the problem is the *boot sector*
that you blanked by the unfortunate "resetting" of the partition. That message
also suggests that the MBR is probably OK.
I am sure most of my data is still on the disk but I cannot read any of
it until I can get the partition table & FAT (file llocation table)
information back. I may also need to write a new mbr, but I don't know.

You better stop the hyper-activity if you wish recovering your data.
I think a copy of a standard MBR & bootsector, needs to be copied to
the first few sectors of the disk, to make it readable again.

Don't do that!
I don't really know how to do this.

Your luck! ;-)
I used a good program by Svend Olaf Mikkelsen - FINDPART - to get a
report (below)

Could anybody tell me if there is any chance of recovering the files on
the hard disk and, if so, how can it be done?

Your data can still be recovered, fully, provided that the reported above is all
you did to the disk and haven't omitted anything.
Findpart, version 4.42.
Copyright Svend Olaf Mikkelsen, 1999-2004.

OS: DOS 7.10

Disk: 1 Cylinders: 785 Heads: 128 Sectors: 63 MB: 3091

I am no expert in deciphering Svend's Findpart results. Just pray that you
haven't blanked the mirror of the boot sector at CHS 0/1/7 and/or the FAT
copies.

RESQDISK could do the job just as well, yet since you started with FINDPART,
then you better stick to what Svend suggests.

Regards, Zvi
 
S

Svend Olaf Mikkelsen

Findpart, version 4.42.
Copyright Svend Olaf Mikkelsen, 1999-2004.

OS: DOS 7.10

Disk: 1 Cylinders: 785 Heads: 128 Sectors: 63 MB: 3091

-PCyl N ID -----Rel -----Num ---MB -Start CHS- --End CHS-- BS CHS
Fdisk F6 sector 0 2 1
Fdisk F6 sector 1 0 1
Fdisk F6 sector 1 1 1
Fdisk F6 sector 2 0 1
Fdisk F6 sector 2 1 1
Fdisk F6 sector 3 0 1
Fdisk F6 sector 3 1 1
0 - 04 3741696 16128 7 464 0 1 465 127 63 B OK
Fdisk F6 sector 586 0 1
Fdisk F6 sector 586 1 1
Fdisk F6 sector 611 0 1
Fdisk F6 sector 611 1 1
0 - 07 63 6330177 3090 0 1 1 784 127 63 BU OK

-----FAT CHS -Size Cl --Root -Good -Rep. Maybe --Bad YYMMDD DataMB
0 1 33 6168 4# 2# 5874 196 0 98 040117 2409
464 0 2 32 1 512 32 0 0 0 040706 2
464 0 34 Second FAT not found.

Partitions according to partition tables on first harddisk:

-PCyl N ID -----Rel -----Num ---MB -Start CHS- --End CHS-- BS CHS
0 1*0C 63 6330177 3090 0 1 1 784 127 63 NB OK

You can insert the disk as disk number 2 in a working Windows system,
and attempt to copy the files to current directory and below (on disk
1) using this command for Findpart for Windows:

findpart chsdir 2 0 1 33 6168 4 2 copy

That command will only work for all files if the directory structure
was not damaged by Fdisk.

If the disk is disk 2, you also can try:

findpart readfat 2 0 1 33 6168 4 2

Some files may be damaged by Fdisk. They can be located among copied
files by searching for files containing strings of ascii 246
characters.

It will be too much to ask me to repair this.
 
P

p-k

Cheers for the replys, lads !!!
and
effective at recovering lost partitions.

I have not tried that yet, but I did try Active uneraser, a partition
recovery tool. It found nothing of any consequence. It sort of "scans"
the disk but I don't think it really worked out that I have not only
deleted the old partition, but I have created a new one with FDISK. I
think that confused the Active uneraser software.
FDISK was a
mistake as it cleared the boot sector and maybe the FAT too!

I am starting to think that using FDISK as designed by Microsoft was a
mistake!!! I will not be using it any more, will probably use OnTrack
Disk Manager, as that is more user-friendly for partitioning disks, and
gives more options + detail.
*boot sector*
that you blanked by the unfortunate "resetting" of the partition. That
message
also suggests that the MBR is probably OK.

I think the first sector might be O.K. because it is not blank. I have
looked at it with sector viewer software. However, sectors 2 - 60
appear to be blank. There are also a few sectors filled with "F6".
that you
haven't blanked the mirror of the boot sector at CHS 0/1/7 and/or the
FAT
copies.

Our Father who art in heaven, Give us this day our daily bread etc.
etc.
I must have been bad for this to happen to me.

Pal, if this works I will donate you some cash!! I will also donate the
same amount to the Tsunami disaster!
I'll give it a whirl and will post the result report in this forum.
Cheers!!
Kind regards
Peter Khan
 
E

Eric Gisin

You can insert the disk as disk number 2 in a working Windows system,
and attempt to copy the files to current directory and below (on disk
1) using this command for Findpart for Windows:

findpart chsdir 2 0 1 33 6168 4 2 copy

That command will only work for all files if the directory structure
was not damaged by Fdisk.

If the disk is disk 2, you also can try:

findpart readfat 2 0 1 33 6168 4 2
What does readfat do? Is there anything to merge fats with some bad sectors?
 
Ad

Advertisements

S

Svend Olaf Mikkelsen

What does readfat do?

It searches the partition, and brings up a file browser, which allows
file copying. Possible options are fat1, fat2, nofat. With "nofat"
copied files will only be correct if they were not fragmented. Without
FAT option the best FAT sector will be chosen if the FAT copies are
different, and only files with FAT will be shown unless the nofat
option is used. The parameters are the disk number, followed by the 6
first numbers from a Findpart FAT search. Files will be copied to
current directory (folder these days) and below.
Is there anything to merge fats with some bad sectors?

Not documented as far as I know.

If the FAT contains bad sectors, and the two FAT copies combined
contains a good FAT, Findpart can repair it, as example for disk 7,
FAT location CHS 10 1 33, FAT size per copy 4544 sectors, the disk has
5654 cylinders (for check):

set findpart=edit
findpart findfat 7 10 1 33 4544 repair 5654

For safety this will only work for a limited number of bad sectors.
The command will not check the entire integrity of the partition, but
that could be done using "Findpart Chsdir" first.

The same command can repair a FAT with hex F6 sectors from Fdisk
damage. In this case further damage had happened, and the command then
will not do the repair.
 
F

Folkert Rienstra

Svend Olaf Mikkelsen said:
It searches the partition, and brings up a file browser, which allows
file copying. Possible options are fat1, fat2, nofat. With "nofat"
copied files will only be correct if they were not fragmented.

So it actually reads the directories then?
Without
FAT option the best FAT sector will be chosen if the FAT copies are
different, and only files with FAT will be shown unless the nofat
option is used. The parameters are the disk number, followed by the 6
first numbers from a Findpart FAT search. Files will be copied to
current directory (folder these days) and below.


Not documented as far as I know.

Presumably because you didn't (document it yet)? ;-)
 
P

p-k

Hi all

I am a happy man at the moment.

As I write, the findpart utility is copying 90% of the files off the
drive which was bootsector blanked by FDISK.

I will update on the situation in due course.

You really seem to know what you are doing Svend. Why do the commercial
software packages not provide the same kind of functionality that yours
does?

I will write-up a report presently.
Kind regards
Peter Khan
 
S

Svend Olaf Mikkelsen

Hi all

I am a happy man at the moment.

As I write, the findpart utility is copying 90% of the files off the
drive which was bootsector blanked by FDISK.

I will update on the situation in due course.

You really seem to know what you are doing Svend. Why do the commercial
software packages not provide the same kind of functionality that yours
does?

I will write-up a report presently.
Kind regards
Peter Khan

Nice so far.

Commercial software should be able to copy these files too.

Findpart is designed so it is possible to get detailed information
about the situation, and to allow hands on recovery work by email, and
in some cases usenet.

Remember that the Findpart Chsdir command does not run a search, it
just follows the directory structure. In some cases entering the Fdisk
create partition screen will damage the directory structure too.
 
P

p-k

Hello Hard Disk Experts
This is a little update to this thread.

I was able to copy most of the files from the damaged disk to a new
disk, and thus recover my most important data. The disk which holds all
the files is now connected via a USB enclosure to my main system and I
am figuring how to back everything up to DVD somehow. I have an
external JAZ drive but for some odd reason either the drive doesn't
seem to be functioning properly or my JAZ disks are bad. But that's
another story.

The moral is always have a back-up device. But I guess it is human
nature not to back-up often enough.

I really am impressed by your knowledge and expertise, Svend. I am a
programmer myself, or at least I dabble around, and I kind of
understand how much effort needs to be put in to get a program
functioning superbly, as yours does.

Put a little user interface on it, write-up a User Manual, and your
software could be a commercial concern. Oh, but don't forget if you
ever think about marketing the disk recovery software, put a massive,
bold-type DISCLAIMER in, so if someone tries to blame your software for
chewing their hard disk, you are legally in the clear!

I have to go now, but I will try to donate some money to you for this
help, Svend - I am really grateful and happy to get my data back. If I
had aproached a data recovery firm I am sure the minimum fee would have
been £100.

Incidentally, is there any reason why those commands (chsdir / readfat)
didn't work from DOS? I initially tried extracting the CHSDIR for DOS,
then the command chsdir 2 0 1 33 6168 4 2 copy d:\ or such variations.
It didn't do much. But when I used the findpart from within Windows,
just as you had said, it worked fine.

Smake på øl !
Skål! Skål! Skål!
I think that is something to do with beer!
Kind regards
Peter Khan
 
Ad

Advertisements

S

Svend Olaf Mikkelsen

Hello Hard Disk Experts
This is a little update to this thread.

I was able to copy most of the files from the damaged disk to a new
disk, and thus recover my most important data. The disk which holds all
the files is now connected via a USB enclosure to my main system and I
am figuring how to back everything up to DVD somehow. I have an
external JAZ drive but for some odd reason either the drive doesn't
seem to be functioning properly or my JAZ disks are bad. But that's
another story.

The moral is always have a back-up device. But I guess it is human
nature not to back-up often enough.

I really am impressed by your knowledge and expertise, Svend. I am a
programmer myself, or at least I dabble around, and I kind of
understand how much effort needs to be put in to get a program
functioning superbly, as yours does.

Put a little user interface on it, write-up a User Manual, and your
software could be a commercial concern. Oh, but don't forget if you
ever think about marketing the disk recovery software, put a massive,
bold-type DISCLAIMER in, so if someone tries to blame your software for
chewing their hard disk, you are legally in the clear!

I have to go now, but I will try to donate some money to you for this
help, Svend - I am really grateful and happy to get my data back. If I
had aproached a data recovery firm I am sure the minimum fee would have
been £100.

Incidentally, is there any reason why those commands (chsdir / readfat)
didn't work from DOS? I initially tried extracting the CHSDIR for DOS,
then the command chsdir 2 0 1 33 6168 4 2 copy d:\ or such variations.
It didn't do much. But when I used the findpart from within Windows,
just as you had said, it worked fine.

Thank you for the comments.

Writing long file names in DOS is not straightforward, so only the
Windows version can copy files.
Smake på øl !
Skål! Skål! Skål!
I think that is something to do with beer!
Kind regards
Peter Khan

Yes. But it is smage for taste.
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Top