chkdsk function for non-Windows partitions

My new PC (Dell/Alienware) has the C: partition assigned to
the NVMe drive (runs like the wind!), but also has four other
partitions for repair, factory restore, etc. None has an assigned
drive letter.

When I back up everything, Acronis reports four bad blocks
were encountered. Chkdsk on C: reports that all is well, so I'm
assuming that, if Acronis is telling the truth, then the
bad blocks must be in one of the other partitions. (Acronis
does back up those four non-standard partitions in addition
to C:.)

Are there tools that will check such partitions? Chkdsk only
allows you to specify a patition with a drive letter assigned.

On Thu, 9 Jan 2020 21:37:31 -0500, Jason
wrote:

My new PC (Dell/Alienware) has the C: partition assigned to
the NVMe drive (runs like the wind!), but also has four other
partitions for repair, factory restore, etc. None has an assigned
drive letter.

When I back up everything, Acronis reports four bad blocks
were encountered. Chkdsk on C: reports that all is well, so I'm
assuming that, if Acronis is telling the truth, then the
bad blocks must be in one of the other partitions. (Acronis
does back up those four non-standard partitions in addition
to C:.)

Are there tools that will check such partitions? Chkdsk only
allows you to specify a patition with a drive letter assigned.

If I was sufficiently concerned, I would temporarily assign a drive letter
to each of those other partitions. Don't be too quick to let chkdsk make
changes, though. It's been known to make things worse from time to time. A
full disk backup would be nice to have in your back pocket in case you make
things worse.

Jason wrote:
My new PC (Dell/Alienware) has the C: partition assigned to
the NVMe drive (runs like the wind!), but also has four other
partitions for repair, factory restore, etc. None has an assigned
drive letter.

When I back up everything, Acronis reports four bad blocks
were encountered. Chkdsk on C: reports that all is well, so I'm
assuming that, if Acronis is telling the truth, then the
bad blocks must be in one of the other partitions. (Acronis
does back up those four non-standard partitions in addition
to C:.)

Are there tools that will check such partitions? Chkdsk only
allows you to specify a patition with a drive letter assigned.


http://www.hdtune.com/files/hdtune_255.exe

You can use the right-most tab, which does a physical layer
scan for bad blocks. (The freebie version of HDTune has
limited device size, and either 1TB or 2TB might be the
max practical size for the tested area. I never bothered to check
and verify what the limit is, but it could be that the software
stopped at 2.2TB for example.) Your NVMe might not be so
excessively large, as to exceed those kinds of limits.

This will give colored blocks, and give you some idea (physically,
percentage of the way out onto the disk), as to what "area" of
the device has the CRC error. You can map that in your mind,
to the partition structure. And that might reduce the amount
of CHKDSKing required. Based on betting odds, the problem is
in C: and not anywhere pesky.

That will tell you, in rough terms, where the CRC errors might
be hiding, and which partition to concentrate your effort.

A CRC error could also "disappear" on you. The NVMe drive has its
own processor and firmware. If using TLC flash, it might attempt to
"freshen" blocks every three months or so, and the re-write of
the data may result in the CRC error going away on its own. The
bad block would be spared out by automatic sparing at the
device level during the rewrite.

CHKDSK accepts C: or it accepts a numeric identifier (the kind
that "mountvol" keeps). Of course, if the identifier is actually
in the output of "mountvol", you would have been using the drive
letter in the first place, so this capability is "cold comfort" and
doesn't really help. I don't know if there is a situation where
you know the identifier and no letter is present, and CHKDSK is
probably cheating and just using "mountvol" to map between the
representations anyway. At first when I read of that, I thought
it had value, but today I'm not convinced it's more than just a
nuisance (teasing you with something you can't have).

If you "expose" a partition by assigning a drive letter, Windows 10
remembers the Mountvol value (somehow) and even if you remove the
drive letter again, diskmgmt.msc will refer to the 0x27 "hidden volume"
via the numeric string. Which is annoying. And may, after all,
allow CHKDSK to it. But I'm not all that happy to see that in
Disk Management, because it also means that maybe System Volume
Information will end up with crap in it, and Windows will start
claiming the (small) partition is out of space.

To expose a partition, requires changing from 0x27 (Hidden NTFS)
to 0x07 (NTFS). In Windows, for MSDOS partitioned disks,
you can use PTEDIT32.exe to change the Sector 0 partition table
information for that byte value. However, your NVMe is unlikely
in the year 2020, to be MSDOS partitioned. It could be GPT partitioned
if this is an OEM computer (even for disks less than 2.2TB they
use it). Using Linux, you may be able to use GDisk to change
the partition type, then boot back into Windows and get to
assign a drive letter. I'm unaware of an equivalent to
PTEDIT32.exe for the massaging of GPT disks in Windows.

sudo gdisk /dev/sda
p # print partition table
(use help for the rest)
w # write out the new values
q # quit

GDisk has a table of values for the GUID Partition table types,
and GPT use two-byte values. At a guess, you'd be changing
a 0x2700 partition to a 0x0700 partition to make it visible.
The second byte is often 00 for most of them, and only
when they wanted "flavors" of common partition types, did
they modify the second byte field.

I don't do a lot of GPT work (it's an evil topic), so
good luck with that :-) You probably won't break anything,
unless you're fooling with the ESP or something. (The ESP
is just a FAT partition, and Tsstdisk.exe can allow you
to list the filenames in *any* mountable partition. TestDisk
is cross-platform, available in both Windows and Linux. I
use it a lot, just for listing filenames in places I'm not
supposed to be looking in.)

On a GPT boot drive, there is one 16MB partition called
Microsoft Reserved. It has no file system. Raw binary blobs
are stored in there. More than one Windows subsystem may use
it. If there's anything important in there (?)... it's
unmaintainable. So let us hope the problem isn't in that
partition, because CHKDSK (nor any other utility) can help.

Paul

"Jason" wrote in message
...
My new PC (Dell/Alienware) has the C: partition assigned to
the NVMe drive (runs like the wind!), but also has four other
partitions for repair, factory restore, etc. None has an assigned
drive letter.

When I back up everything, Acronis reports four bad blocks
were encountered. Chkdsk on C: reports that all is well, so I'm
assuming that, if Acronis is telling the truth, then the
bad blocks must be in one of the other partitions. (Acronis
does back up those four non-standard partitions in addition
to C:.)

Are there tools that will check such partitions? Chkdsk only
allows you to specify a patition with a drive letter assigned.

Boot from the Acronis CD and do your backup that way. If it has any errors,
it will let you know. It may just be a Windows thing.

I have found it easier and quicker using that method rather than installing
and running Acronis within Windows.
--

SC Tom

In article ,
lid says...
A
full disk backup would be nice to have in your back pocket in case you make
things worse.

I never leave home without one...! Thanks for the cautions. I'm
aware that chkdsk can do damage; it happened to me once. Only -then-
did I read up on that.

In article , says...
Boot from the Acronis CD and do your backup that way. If it has any errors,
it will let you know. It may just be a Windows thing.

I have found it easier and quicker using that method rather than installing
and running Acronis within Windows.

Alas, no CD on this new machine, but I do use the Acronis startup (F11)
function and occasionally launch backups that way. I haven't tried that
recently - I will and see if the errors are still reported.

In article , lid says...
This will give colored blocks, and give you some idea (physically,
percentage of the way out onto the disk), as to what "area" of
the device has the CRC error.


I have watched carefully and Task Manager indirectly confirms that
the errors are reported the very instant that Acronis finishes with
the spinning drive and begins backing up the NVMe drive - that's why
I'm suspicious that the error (if real) is NOT on C:, but on one of
those other partitions.

Jason wrote:
In article , lid says...
This will give colored blocks, and give you some idea (physically,
percentage of the way out onto the disk), as to what "area" of
the device has the CRC error.

I have watched carefully and Task Manager indirectly confirms that
the errors are reported the very instant that Acronis finishes with
the spinning drive and begins backing up the NVMe drive - that's why
I'm suspicious that the error (if real) is NOT on C:, but on one of
those other partitions.

Why not - temporarily - back up one partition at a time, so you *know*
which partition is the problem?

A little earlier, I wrote:
Jason wrote:
In article , lid says...
This will give colored blocks, and give you some idea (physically,
percentage of the way out onto the disk), as to what "area" of
the device has the CRC error.

I have watched carefully and Task Manager indirectly confirms that
the errors are reported the very instant that Acronis finishes with
the spinning drive and begins backing up the NVMe drive - that's why
I'm suspicious that the error (if real) is NOT on C:, but on one of
those other partitions.

Why not - temporarily - back up one partition at a time, so you *know*
which partition is the problem?

BTW, doesn't Acronis have a log file which tells you these things
(i.e. what error occured when)?

I use Macrium and just have to click the 'Log' button to see the
latest and earlier log files.

"Jason" wrote in message
...
In article , says...
Boot from the Acronis CD and do your backup that way. If it has any
errors,
it will let you know. It may just be a Windows thing.

I have found it easier and quicker using that method rather than
installing
and running Acronis within Windows.

Alas, no CD on this new machine, but I do use the Acronis startup (F11)
function and occasionally launch backups that way. I haven't tried that
recently - I will and see if the errors are still reported.


So the PC came with Acronis? Pretty cool!
I assume the F11 Acronis startup brings up the Acronis GUI? Does it give you
a choice of "Start Windows", "Start Acronis", "Acronis System Report"?
That's what the bootable CD starts with.
IIRC, you can create a bootable CD from within the ATI program, or, if the
installed copy is registered with Acronis, you can log into your account
online and download the bootable media. Might be nice to have just in case.
You never know when you could have a catastrophic drive disaster.

In article , says...

So the PC came with Acronis? Pretty cool!
I assume the F11 Acronis startup brings up the Acronis GUI? Does it give you
a choice of "Start Windows", "Start Acronis", "Acronis System Report"?
That's what the bootable CD starts with.
IIRC, you can create a bootable CD from within the ATI program, or, if the
installed copy is registered with Acronis, you can log into your account
online and download the bootable media. Might be nice to have just in case.
You never know when you could have a catastrophic drive disaster.

It didn't come with Acronis. I downloaded it. I have a rescue disk and
thumb drive already - I use Acronis on my laptop which does have a CD
drive. F11 at boot starts the same version you see when you boot the CD.

In article ,
lid says...
Why not - temporarily - back up one partition at a time, so you *know*
which partition is the problem?

Acronis only offers to back up partitons with an assigned drive letter
:-(

In article ,
lid says...
BTW, doesn't Acronis have a log file which tells you these things
(i.e. what error occured when)?

It creates extensive logs, but nothing I found in them narrows down
the error.

Jason wrote:
In article ,
lid says...
Why not - temporarily - back up one partition at a time, so you *know*
which partition is the problem?

Acronis only offers to back up partitons with an assigned drive letter
:-(

But as Char Jackson suggested, you can temporarily assign drive
letters to those partitions which don't have one.

Jason wrote:
My new PC (Dell/Alienware) has the C: partition assigned to
the NVMe drive (runs like the wind!), but also has four other
partitions for repair, factory restore, etc. None has an assigned
drive letter.

When I back up everything, Acronis reports four bad blocks
were encountered. Chkdsk on C: reports that all is well, so I'm
assuming that, if Acronis is telling the truth, then the
bad blocks must be in one of the other partitions. (Acronis
does back up those four non-standard partitions in addition
to C:.)

I think this has not been mentioned yet: 'chkdsk' does *not* check for
bad sectors (unless you use the /R (or /B) option, which is very time
consuming). I.e. 'chkdsk' only checks the 'bookkeeping' of the file
system, but does *not* read/check each data sector. (I don't know how
the concept of 'bad sectors' applies to NVMe drives. Just described the
situation for normal hard-disks.)

So your assumption that C: has no bad sectors might be incorrect.

Are there tools that will check such partitions? Chkdsk only
allows you to specify a patition with a drive letter assigned.