Recovery boot sector of logical partition

[science2003]

I have a HD of 60 gb splitted in two FAT32 partitions (HD1 primary
28.7Gb and HD2 logical 29.7Gb ). The HD is used as slave, and it is not
the bootable HD in my PC.

Disaster striked when, in a "normal" starting up, without apparent
reasons, the drive HD2 in Computer resources appeared as RAW, asking if
touched to be formatted. (It was almost full of data).

I checked with an utility and it appears that the very first sector
(S1) of the drive HD2 logical partition gives error (C.3697, H1 S1).
When with an editor I checked this sector I have the following message
"An Error occured while reading from absolute sector 59392368" (i.e
corrisponding to C 3697, H1, S1). Is there something that I can do to
regain HD2? Can I remove the sector above and tell the system to check
from the next sector? Is there some utility that can be helpful
(Partition Table Doctor was unable to fix the boot sector). Thanks for
your time

 

[Folkert Rienstra]

I have a HD of 60 gb split in two FAT32 partitions (HD1 primary
28.7Gb and HD2 logical 29.7Gb ). The HD is used as slave, and it is not
the bootable HD in my PC.

Disaster stroke when, in a "normal" starting up, without apparent
reasons, the drive HD2 in Computer resources appeared as RAW,
asking if touched to be formatted. (It was almost full of data).

I checked with an utility and it appears that the very first sector
(S1) of the drive HD2 logical partition gives error (C.3697, H1 S1).

Actually, that is the partition bootsector, not the first sector and not
the first data sector either.

When with an editor I checked this sector I have the following message
"An Error occurred while reading from absolute sector 59392368" (ie
corresponding to C 3697, H1, S1).

Is there something that I can do to regain HD2?
Probably.

Can I remove the sector above
No.

and tell the system to check from the next sector?

What's the point. It's the partition bootsector. You can't just do without
(though in theory you should and some older OS indeed do, but not the later ones).

FAT32 has a backup bootsector usually 6 sectors behind the original.
You need a Hex sector editor that can copy the backup sector contents
and is capable and dump it to the original destination without reading
the contents from that original destination first.

Is there some utility that can be helpful (Partition Table Doctor was
unable to fix the boot sector).

Yes, no positives for that one yet.

 

[Joep]

I have a HD of 60 gb splitted in two FAT32 partitions (HD1 primary
28.7Gb and HD2 logical 29.7Gb ). The HD is used as slave, and it is not
the bootable HD in my PC.

Disaster striked when, in a "normal" starting up, without apparent
reasons, the drive HD2 in Computer resources appeared as RAW, asking if
touched to be formatted. (It was almost full of data).

I checked with an utility and it appears that the very first sector
(S1) of the drive HD2 logical partition gives error (C.3697, H1 S1).
When with an editor I checked this sector I have the following message
"An Error occured while reading from absolute sector 59392368" (i.e
corrisponding to C 3697, H1, S1). Is there something that I can do to
regain HD2? Can I remove the sector above and tell the system to check
from the next sector? Is there some utility that can be helpful
(Partition Table Doctor was unable to fix the boot sector). Thanks for
your time

You can probably, like F.R. suggested use a diske editor and copy the backup
boot sector to the corrupt sector. If you feel uncomfortable using a disk
editor I can help:

Get DiskPatch from www.diydatarecovery.nl > with DiskPatch create a support
log > post the log in the forum on our website (again
www.diydatarecovery.nl).

Joep

 

[science2003]

Many thanks for your answers.
To F.R.: Thanks, yes, indeed is the partition bootsector. (sorry, I am
a new DIY, not an expert). A point that seems important is that when I
tested the surface of the HD, this first partition bootsector gives me
"Verify sector error at:59392368". It seems therefore that the HD is
not able to read that sector, not just that it is corrupted. Am I
correct?

To Joep: Many thanks for your support. I will certainly try to post the
log. But giving the "surface test" do you really think that it is
possible to edit that sector?

 

[science2003]

Sorry just an update:
As F.R. suggested 6 sectors after S1 (i.e. S7) there is "something" and
S2 and S8 are the same (by the way this is not true for S3&S4 and
S9&10). I saved S7 with Partition Table Doctor 3 (that is what I have,
probably Joep's Utility is better but I have only the trial). I was
tempted to Restore the saved sector S7 in S1. I had several warnings by
PTD that this may destroy all data. So I stopped and I am asking now to
you. Shall I go on?

 

[Joep]

Sorry just an update:
As F.R. suggested 6 sectors after S1 (i.e. S7) there is "something" and
S2 and S8 are the same (by the way this is not true for S3&S4 and
S9&10). I saved S7 with Partition Table Doctor 3 (that is what I have,
probably Joep's Utility is better
Yes.

but I have only the trial). I was
tempted to Restore the saved sector S7 in S1. I had several warnings by
PTD that this may destroy all data. So I stopped and I am asking now to
you. Shall I go on?

Yes. It will not destroy all data. You can not detroy all data when writing
to just this one sector.

 

[wemaole]

Maybe you need ask (e-mail address removed)

 

[Folkert Rienstra]

Sorry just an update:
As F.R. suggested 6 sectors after S1 (i.e. S7) there is "something" and
S2 and S8 are the same (by the way this is not true for S3&S4 and
S9&10). I saved S7 with Partition Table Doctor 3 (that is what I have,
probably Joep's Utility is better but I have only the trial). I was
tempted to Restore the saved sector S7 in S1.

I had several warnings by PTD that this may destroy all data.

That's nonsense.
That only applies to a working good partition with a corrupted backup boot-
sector. And recovery will still be possible by smarter utilities than PTD.

So I stopped and I am asking now to you.
Shall I go on?

Yes, on the presumption that PTD won't **** up on that simple action.

 

[Folkert Rienstra]

Many thanks for your answers.
To F.R.: Thanks, yes, indeed is the partition bootsector. (sorry, I am
a new DIY, not an expert).

Your subject line was actually correct.

A point that seems important is that when I
tested the surface of the HD, this first partition bootsector gives me
"Verify sector error at:59392368".

It seems therefore that the HD is not able to read that sector, not
just that it is corrupted.

Am I correct?

Both is correct. The drive can't read it because the calculated ECC and
the recorded ECC differ, meaning the sector cannot be reliably read,
meaning contents is not reliable, i.e. corrupt. Also known as a bad sector.

If this state persists it can only be corrected by overwriting the sector.
In this case by using the contents of the back-up bootsector.

To Joep: Many thanks for your support. I will certainly try to post the
log. But giving the "surface test" do you really think that it is possible to
edit that sector?

Not if it stays persistently bad.

 

[Folkert Rienstra]

Maybe you need ask (e-mail address removed)

Or in other words, you don't trust yourself to answer it here in public, PTD spam bot.

 

[Zvi Netiv]

Sorry just an update:
As F.R. suggested 6 sectors after S1 (i.e. S7) there is "something" and
S2 and S8 are the same (by the way this is not true for S3&S4 and
S9&10). I saved S7 with Partition Table Doctor 3 (that is what I have,
probably Joep's Utility is better but I have only the trial). I was
tempted to Restore the saved sector S7 in S1. I had several warnings by
PTD that this may destroy all data. So I stopped and I am asking now to
you. Shall I go on?

You don't risk much by attempting to rewrite that single sector, but I doubt
that it will work.

If the data in the inaccessible partition is worth the cost of a new drive, and
the overwriting of the boot sector fails, then I recommend that you clone the
drive to a new one, in good working condition, and that you finish the recovery
on the clone.

Regards, Zvi

 

[Joep]

You don't risk much by attempting to rewrite that single sector, but I doubt
that it will work.

Hmm ... you may be right but I am pretty optimistic that it can be
reallocated. It's worth the try.

 

[science2003]

Well, let me update

shall I go on?
Yes....

So I did, and I got it (touching wood): The logical partition has been
claimed back at the next reboot. Thank you to all of you very much
indeed.
I run next chkdsk \v and the partition is not really perfect. 32K of
disk error. Do you want to correct it and make CHK? Y/N: N!
And I said no because I read during the past night Joep's product
DiskPatch manual. Yes, I learnt a lot of things and I shall
congratulate of what DP is able to do. But it is all DOS! To be
assured, I brought the product to a geek in the IT department. He knew
your product and I asked him to made the log of my HD for me (then I
take the courage myself and I did the patch).
DP is able to correct better sector errors than chkdsk does, I learnt,
so I would probably bring the product back the IT dep. to make a
general block check before I am using it (I need a bit of wait for
this).
Two general considerations that may help other people: from DP manual:
1 scandisk and checkdisk "main job is to keep the filesystem okay, not
the actual data that resides on the disk." So is there an alternative
that can be run within Windows that allows chkdsk \Fix undos or that
ask before making changes to structure that may lose data, telling what
will be lost?
2. For a parallel ATA HD used to store data in a mobile rack and that
is swaped to different PCs (with WIn2000 e WinXP), what is the best
format to minimize the above losses: NTFS or FAT32. And is it better to
have two primary or one primary and one logical parititon?
Many thanks again

 

[Folkert Rienstra]

Well, let me update
So I did, and I got it (touching wood): The logical partition has been
claimed back at the next reboot. Thank you to all of you very much
indeed.
I run next chkdsk \v and the partition is not really perfect. 32K of
disk error. Do you want to correct it and make CHK? Y/N: N!
And I said no because I read during the past night Joep's product
DiskPatch manual. Yes, I learnt a lot of things and I shall
congratulate of what DP is able to do. But it is all DOS! To be
assured, I brought the product to a geek in the IT department. He knew
your product and I asked him to made the log of my HD for me (then I
take the courage myself and I did the patch).

DP is able to correct better sector errors than chkdsk does, I learnt,

Oh, in what way?

 

[Folkert Rienstra]

You don't risk much by attempting to rewrite that single sector, but I doubt
that it will work.

That's because you *still* don't know how harddrives work.

If the data in the inaccessible partition is worth the cost of a new drive,

and the overwriting of the boot sector fails,

For that to happen the drive must be dead as a doornail. It obviously isn't.

then I recommend that you clone the drive to a new one,

Clone a 'dead as a doornail' drive? You must be kidding.

in good working condition, and that you finish the recovery on the clone.

For one single bad sector -that likely isn't even bad, just badly written-,
that's totally mad.

 

[Joep]

That's because you *still* don't know how harddrives work.
drive,

For that to happen the drive must be dead as a doornail. It obviously isn't.

Clone a 'dead as a doornail' drive? You must be kidding.

FYI: I have seen disks that did no longer seem to reallocate and still could
be cloned. It is not as exceptional as you make it sound. They were more
alive than a doornail.

Joep

 

[Rod Speed]

Well, let me update
So I did, and I got it (touching wood): The logical partition has been
claimed back at the next reboot. Thank you to all of you very much
indeed.
I run next chkdsk \v and the partition is not really perfect. 32K of
disk error. Do you want to correct it and make CHK? Y/N: N!
And I said no because I read during the past night Joep's product
DiskPatch manual. Yes, I learnt a lot of things and I shall
congratulate of what DP is able to do. But it is all DOS! To be
assured, I brought the product to a geek in the IT department. He knew
your product and I asked him to made the log of my HD for me (then I
take the courage myself and I did the patch).
DP is able to correct better sector errors than chkdsk does, I learnt,
so I would probably bring the product back the IT dep. to make a
general block check before I am using it (I need a bit of wait for
this).

Two general considerations that may help other people: from DP manual:
1 scandisk and checkdisk "main job is to keep the filesystem okay, not
the actual data that resides on the disk." So is there an alternative
that can be run within Windows that allows chkdsk \Fix undos or that
ask before making changes to structure that may lose data, telling
what will be lost?

The safest approach is to clone the drive to another
before trying various tools to recover what data you can.

And chkdsk is very undesirable, there are plenty better tools around
for file recovery. I like EasyRecovery Pro myself, but it aint free.

2. For a parallel ATA HD used to store data in a mobile rack and
that is swaped to different PCs (with WIn2000 e WinXP), what is
the best format to minimize the above losses: NTFS or FAT32.
NTFS.

And is it better to have two primary or
one primary and one logical parititon?

Doesnt really matter much, two primarys is a bit simpler.

 

[Rod Speed]

That's because you *still* don't know how harddrives work.



For that to happen the drive must be dead as a doornail. It obviously
isn't.


Clone a 'dead as a doornail' drive? You must be kidding.

For one single bad sector

You dont know that yet.

-that likely isn't even bad, just badly written-,

Or that.

that's totally mad.

Nope, it allows you to try various recovery tools/

 

[Zvi Netiv]

(e-mail address removed) wrote:

[...]

If the data in the inaccessible partition is worth the cost of a new drive,
and the overwriting of the boot sector fails,

For that to happen the drive must be dead as a doornail. It obviously isn't.

Then I must have recovered many "dead" drives. ;-) With all due respect, you
don't have the slightest idea on what you are talking about.

Clone a 'dead as a doornail' drive? You must be kidding.


For one single bad sector -that likely isn't even bad, just badly written-,
that's totally mad.

Would you mind explaining how come that a boot sector that was written time ago,
and was functioning properly since its creation, became all in a sudden "badly
written"?

Get this, blockhead: Boot sectors aren't rewritten occasionally and don't
become bad because they were "badly written". In many cases, such incident may
predict an imminent disk failure.

 

[science2003]

Am I wrong, or the File Allocation (i.e. Order) Table of our messages
is not quite right. Any way thank you again for this discussion.