Erasing USB flash drives?

Has anyone come across a program that quick erases a USB flash drive stick,
so that a simple unerase program doesn't show what files were on it? (I
don't do this for security reasons, I only do it for my own convenience
(when I'm trying to recall what changes I make on the drive subsequentially;
it's hard to explain :-).

So here is what I have discovered:
"Eraser" doesn't seem to be able to do it for flash dirves, although it
works well on other drives. (I'm just talking about using the basic erase
options here)

The WinXP disk defragger(s) don't do it, either.

BUT the standard Win98/ME defragger DOES do it! And you only have to run it
for a few seconds to clear traces of any file entries; it doesn't need to
run to completion.

Clearly the Win98/ME defrag works a lot better in that one regard (on FAT
volumes) than the WinXP defragger(s) do. It somehow erases the FAT table
entries, where the Win XP defraggers don't.

"Bill in Co" wrote in message
...
Has anyone come across a program that quick erases a USB flash drive
stick, so that a simple unerase program doesn't show what files were on
it? (I don't do this for security reasons, I only do it for my own
convenience (when I'm trying to recall what changes I make on the drive
subsequentially; it's hard to explain :-).

So here is what I have discovered:
"Eraser" doesn't seem to be able to do it for flash dirves, although it
works well on other drives. (I'm just talking about using the basic
erase options here)

The WinXP disk defragger(s) don't do it, either.

BUT the standard Win98/ME defragger DOES do it! And you only have to
run it for a few seconds to clear traces of any file entries; it doesn't
need to run to completion.

Clearly the Win98/ME defrag works a lot better in that one regard (on
FAT volumes) than the WinXP defragger(s) do. It somehow erases the FAT
table entries, where the Win XP defraggers don't.



Unless I'm missing your point, plug in the flash drive, right click on the
drive letter and format it.
--
Bruce Hagen
MS-MVP Oct. 1, 2004 ~ Sept. 30, 2010
Imperial Beach, CA

Bruce Hagen wrote:
"Bill in Co" wrote in message
...
Has anyone come across a program that quick erases a USB flash drive
stick, so that a simple unerase program doesn't show what files were on
it? (I don't do this for security reasons, I only do it for my own
convenience (when I'm trying to recall what changes I make on the drive
subsequentially; it's hard to explain :-).

So here is what I have discovered:
"Eraser" doesn't seem to be able to do it for flash dirves, although it
works well on other drives. (I'm just talking about using the basic
erase options here)

The WinXP disk defragger(s) don't do it, either.

BUT the standard Win98/ME defragger DOES do it! And you only have to
run it for a few seconds to clear traces of any file entries; it doesn't
need to run to completion.

Clearly the Win98/ME defrag works a lot better in that one regard (on
FAT volumes) than the WinXP defragger(s) do. It somehow erases the FAT
table entries, where the Win XP defraggers don't.



Unless I'm missing your point, plug in the flash drive, right click on the
drive letter and format it.

OK, my bad, I didn't explain it correctly.

I want to do this on flash drives that already have data that I wish to
preserve. Let me explain:

I have some USB flash drives where I might decide to add some files, then
later delete them, and want it to look as if I hadn't added them (i.e. a
clean slate) for the next experiment. And the way I check that is: to run
an unerase program to see what was left there, and what's not, and what I've
just recently erased . To do this, I need the drive to appear to be cleaned
(of those entries) before the next test. I guess I'm having a hard time
explaining this. :-)

"Bill in Co" wrote in message
m...
Bruce Hagen wrote:
"Bill in Co" wrote in message
...
Has anyone come across a program that quick erases a USB flash drive
stick, so that a simple unerase program doesn't show what files were
on
it? (I don't do this for security reasons, I only do it for my own
convenience (when I'm trying to recall what changes I make on the
drive
subsequentially; it's hard to explain :-).

So here is what I have discovered:
"Eraser" doesn't seem to be able to do it for flash dirves, although
it
works well on other drives. (I'm just talking about using the basic
erase options here)

The WinXP disk defragger(s) don't do it, either.

BUT the standard Win98/ME defragger DOES do it! And you only have to
run it for a few seconds to clear traces of any file entries; it
doesn't
need to run to completion.

Clearly the Win98/ME defrag works a lot better in that one regard (on
FAT volumes) than the WinXP defragger(s) do. It somehow erases the
FAT
table entries, where the Win XP defraggers don't.



Unless I'm missing your point, plug in the flash drive, right click on
the
drive letter and format it.

OK, my bad, I didn't explain it correctly.

I want to do this on flash drives that already have data that I wish to
preserve. Let me explain:

I have some USB flash drives where I might decide to add some files,
then later delete them, and want it to look as if I hadn't added them
(i.e. a clean slate) for the next experiment. And the way I check that
is: to run an unerase program to see what was left there, and what's
not, and what I've just recently erased . To do this, I need the drive
to appear to be cleaned (of those entries) before the next test. I
guess I'm having a hard time explaining this. :-)



I think I understand you now. I don't know of any program. If there isn't
any, use multiple flash drives.

Eg: Drive 1 has 4 files A B C D. You want to save only C & D. Drag them to
another flash drive (2) and format the original. Add E & F to the
formatted drive and copy back C & D. Format drive 2 and so on.
--
Bruce Hagen
MS-MVP Oct. 1, 2004 ~ Sept. 30, 2010
Imperial Beach, CA

Bill in Co wrote:

I have some USB flash drives where I might decide to add some files, then
later delete them, and want it to look as if I hadn't added them (i.e. a
clean slate) for the next experiment. And the way I check that is: to run
an unerase program to see what was left there, and what's not, and what I've
just recently erased . To do this, I need the drive to appear to be cleaned
(of those entries) before the next test. I guess I'm having a hard time
explaining this. :-)

Wouldn't any tool that wipes "free space" do what you want? There would
be nothing remnant in the media in that unused space (which is where
were the files that you then deleted).

When you delete the file, it is no longer in the file table. That
doesn't wipe the sectors that the files used that are now deleted. So
you need something that works outside the file table to wipe the sectors
that are now free but were previously used and may still contain data.

"Bill in Co" wrote in message
m...
Bruce Hagen wrote:
"Bill in Co" wrote in message
...
Has anyone come across a program that quick erases a USB flash drive
stick, so that a simple unerase program doesn't show what files were
on
it? (I don't do this for security reasons, I only do it for my own
convenience (when I'm trying to recall what changes I make on the
drive
subsequentially; it's hard to explain :-).

So here is what I have discovered:
"Eraser" doesn't seem to be able to do it for flash dirves, although
it
works well on other drives. (I'm just talking about using the basic
erase options here)

The WinXP disk defragger(s) don't do it, either.

BUT the standard Win98/ME defragger DOES do it! And you only have
to
run it for a few seconds to clear traces of any file entries; it
doesn't
need to run to completion.

Clearly the Win98/ME defrag works a lot better in that one regard
(on
FAT volumes) than the WinXP defragger(s) do. It somehow erases the
FAT
table entries, where the Win XP defraggers don't.



Unless I'm missing your point, plug in the flash drive, right click
on the
drive letter and format it.

OK, my bad, I didn't explain it correctly.

I want to do this on flash drives that already have data that I wish
to preserve. Let me explain:

I have some USB flash drives where I might decide to add some files,
then later delete them, and want it to look as if I hadn't added them
(i.e. a clean slate) for the next experiment. And the way I check
that is: to run an unerase program to see what was left there, and
what's not, and what I've just recently erased . To do this, I need
the drive to appear to be cleaned (of those entries) before the next
test. I guess I'm having a hard time explaining this. :-)

So, what happens when you try to do it with Eraser? Does it fail with
an error message? Does it hang? Does it complete as if it has
succeeded but the undelete program still sees the files?
--
Glen Ventura
MS MVP Oct. 2002 - Sept. 2009
CompTIA A+

glee wrote:
"Bill in Co" wrote in message
m...
Bruce Hagen wrote:
"Bill in Co" wrote in message
...
Has anyone come across a program that quick erases a USB flash drive
stick, so that a simple unerase program doesn't show what files were
on
it? (I don't do this for security reasons, I only do it for my own
convenience (when I'm trying to recall what changes I make on the
drive
subsequentially; it's hard to explain :-).

So here is what I have discovered:
"Eraser" doesn't seem to be able to do it for flash dirves, although
it
works well on other drives. (I'm just talking about using the basic
erase options here)

The WinXP disk defragger(s) don't do it, either.

BUT the standard Win98/ME defragger DOES do it! And you only have
to
run it for a few seconds to clear traces of any file entries; it
doesn't
need to run to completion.

Clearly the Win98/ME defrag works a lot better in that one regard
(on
FAT volumes) than the WinXP defragger(s) do. It somehow erases the
FAT
table entries, where the Win XP defraggers don't.



Unless I'm missing your point, plug in the flash drive, right click
on the
drive letter and format it.

OK, my bad, I didn't explain it correctly.

I want to do this on flash drives that already have data that I wish
to preserve. Let me explain:

I have some USB flash drives where I might decide to add some files,
then later delete them, and want it to look as if I hadn't added them
(i.e. a clean slate) for the next experiment. And the way I check
that is: to run an unerase program to see what was left there, and
what's not, and what I've just recently erased . To do this, I need
the drive to appear to be cleaned (of those entries) before the next
test. I guess I'm having a hard time explaining this. :-)

So, what happens when you try to do it with Eraser? Does it fail with
an error message? Does it hang? Does it complete as if it has
succeeded but the undelete program still sees the files?

Eraser runs fine, but it just doesn't remove the file list.
I use the erase (overwrite) unused space directory entries option, which
works great, EXCEPT on flash drives. It's very fast and works great on most
disks. (I'm not trying to go through and erase all remnants (i.e. for
security reasons), which is a completely different scenario -just the
directory entries.

IIRC, there was actually a note on their web site (and some other sites)
that admits this is a difficult task to accomplish with flash drives, due to
their wear leveling routines (moving the stored "locations" around after
each rewrite for wear leveling).

VanguardLH wrote:
Bill in Co wrote:

I have some USB flash drives where I might decide to add some files, then
later delete them, and want it to look as if I hadn't added them (i.e. a
clean slate) for the next experiment. And the way I check that is: to
run
an unerase program to see what was left there, and what's not, and what
I've
just recently erased . To do this, I need the drive to appear to be
cleaned
(of those entries) before the next test. I guess I'm having a hard time
explaining this. :-)

Wouldn't any tool that wipes "free space" do what you want?

Evidently not, at least not with these USB flash drives, as I mentioned in
the other post I just sent. What isn't getting erased evidently is the FAT
table as far as I can see this. (I'm not talking about any partial
remnants of files on the disk which have been subsequentally marked as being
available free space).

There would
be nothing remnant in the media in that unused space (which is where
were the files that you then deleted).

When you delete the file, it is no longer in the file table.

That's what one would assume, and that those file tables entries are gone.

That doesn't wipe the sectors that the files used that are now deleted.

That's not what I need, though. (The file name entries are evidently still
showing up in the FAT table when scanned by an unerase program).

So
you need something that works outside the file table to wipe the sectors
that are now free but were previously used and may still contain data.

"Bill in Co" wrote in message
m...
glee wrote:
"Bill in Co" wrote in message
m...
Bruce Hagen wrote:
"Bill in Co" wrote in message
...
Has anyone come across a program that quick erases a USB flash
drive
stick, so that a simple unerase program doesn't show what files
were
on
it? (I don't do this for security reasons, I only do it for my
own
convenience (when I'm trying to recall what changes I make on the
drive
subsequentially; it's hard to explain :-).

So here is what I have discovered:
"Eraser" doesn't seem to be able to do it for flash dirves,
although
it
works well on other drives. (I'm just talking about using the
basic
erase options here)

The WinXP disk defragger(s) don't do it, either.

BUT the standard Win98/ME defragger DOES do it! And you only have
to
run it for a few seconds to clear traces of any file entries; it
doesn't
need to run to completion.

Clearly the Win98/ME defrag works a lot better in that one regard
(on
FAT volumes) than the WinXP defragger(s) do. It somehow erases
the
FAT
table entries, where the Win XP defraggers don't.



Unless I'm missing your point, plug in the flash drive, right click
on the
drive letter and format it.

OK, my bad, I didn't explain it correctly.

I want to do this on flash drives that already have data that I wish
to preserve. Let me explain:

I have some USB flash drives where I might decide to add some files,
then later delete them, and want it to look as if I hadn't added
them
(i.e. a clean slate) for the next experiment. And the way I check
that is: to run an unerase program to see what was left there, and
what's not, and what I've just recently erased . To do this, I need
the drive to appear to be cleaned (of those entries) before the next
test. I guess I'm having a hard time explaining this. :-)

So, what happens when you try to do it with Eraser? Does it fail
with
an error message? Does it hang? Does it complete as if it has
succeeded but the undelete program still sees the files?

Eraser runs fine, but it just doesn't remove the file list.
I use the erase (overwrite) unused space directory entries option,
which works great, EXCEPT on flash drives. It's very fast and works
great on most disks. (I'm not trying to go through and erase all
remnants (i.e. for security reasons), which is a completely different
scenario -just the directory entries.

IIRC, there was actually a note on their web site (and some other
sites) that admits this is a difficult task to accomplish with flash
drives, due to their wear leveling routines (moving the stored
"locations" around after each rewrite for wear leveling).


I don't think an undelete program will show you files that are
recoverable if all it sees is the index, the list... but not the data
itself that can be recovered. What I'm saying is, you are trying to get
Eraser to just delete the file list.... that's not what is does, as I
recall, it overwrites the actual data on disk. If you still see the
file listed by the undeleter, then the data itself is still available.

It sounds like you only want to delete the file list of names but not
the data itself.... AFAIK Eraser doesn't do that in the first place.
Eraser was developed primarily to overwrite the data. Are you using
some other option in Eraser that purports to remove file names but not
overwrite the data? I don't see why Eraser would even have that option
since it is designed for security purposes to overwrite the actual data.

The last time I used Eraser was over 10 years ago, so perhaps it
changed, but from the readme file of that version:

"Eraser is an advanced security tool, which allows you to completely
remove sensitive data from your hard drive by overwriting it several
times with carefully selected patterns..... The patterns used for
overwriting are based on Peter Gutmann's paper "Secure Deletion of Data
from Magnetic and Solid-State Memory" and they are selected to
effectively remove the magnetic remnants from the hard disk making it
impossible to recover the data. Other methods include the one defined
in the National Industrial Security Program Operating Manual of the US
Department of Defense and overwriting with pseudo-random data up to one
hundred times."

I don't see any mention of it having an option to remove files from the
list without overwriting the data. It sounds like it is just being
unsuccessful working on your flash memory for other reasons.
--
Glen Ventura
MS MVP Oct. 2002 - Sept. 2009
CompTIA A+

The default file system for removable media is FAT. There are 2 copies
of the FAT (file allocation table) to provide redundancy checking. That
an old entry is in the duplicate FAT shouldn't be seen by normal apps -
but then you're not using a normal app as it is not just issuing system
API calls regarding FAT entries but actually digging into the FAT at a
low-level to go look in the duplicate and unused copy.

The 2 copies of the FAT are tightly synchronized on writes to ensure
they have equal allocations of which clusters belong to which file.
However, on reads, the 2nd copy is only used when error occur in the 1st
FAT copy. The 2nd copy is so infrequently used that it might as well as
not exist. Even disk repair tools don't use the 2nd FAT.

Normally there are 2 copies of the FAT but a boot sector (byte 16) can
specify the number of copies (1 or 2; default is 2). See
http://www.win.tue.nl/~aeb/linux/fs/fat/fat-1.html, section 1.2, Boot
Sector. For FAT12 or FAT16, only the first or primary FAT gets used and
the 2nd is ignored but kept in sync. For FAT32, you could select which
copy was the primary FAT. That meant you could switch between FATs if
one got corrupt by changing a 4-bit value within the Flags field (never
had to do that so I don't of any handy tools for switching between
primary and backup FATs under FAT32). Other than a disk editor (where
you can look at and edit any sector on the disk), I didn't bother
searching around for tools that would let the user configure whether or
not there was the 2nd or duplicate FAT copy. When you delete a file,
its entry is removed from the primary FAT copy. I would've expected the
2nd copy to get updated, too, but apparently not in your case. Since
you are writing to the primary FAT when removing a file's entry there,
the write operation should mandate a synchronization of the backup FAT.
For some reason, perhaps your FAT copies are getting out of sync.

While I remember from long ago in my MS-DOS days that the 2nd FAT could
be used to replace the 1st FAT if the 1st FAT got corrupted, I never had
to do that. So I don't know of any tools that replace the 1st FAT with
the 2nd FAT. There is mention of using a hex editor to manually sync
(http://www.microswamp.com/index.php?...s/article&rn=3)
the 1st FAT from entries in the backup FAT so I imagine there are tools
that will automatically overwrite the 1st FAT with the contents of the
backup FAT.

There is some info at http://averstak.tripod.com/fatdox/bootsec.htm
about the boot sector entries that affect behavior of the FAT. Search
on "sync" and note the article mentions that a flag can be used to
determine if the 2 FATs are kept in sync or not, how it is normally
unset (zeroed) but that disk tools might set it to fix problems;
however, if the bit remained set then subsequent synchronization won't
occur and the FATs will get out of sync. I suppose it's even possible
for tweaking every ounce of performance out of the device that the
manufacturer could disable synchronization to eliminate the overhead of
having to update 2 copies of the FAT during writes to the primary one.
I've seen some articles talking about disk utilities or low-level
commands (that bypass the system API) where they can exit with or
without synchronizing the FATs.

So it looks like your unerase utility is finding old entries in the 2nd
copy of the FAT for files that no longer exist either because you
deleted them or even after wiping free space to completely eradicate the
*file* contents. As has been mentioned, formatting will wipe the drive
and leave you with an empty FAT, including the 2nd one. Maybe even a
quick format would create new FATs (primary and backup) since you
already did the free space wipe.

So it looks like the first respondent, Bruce, had the easiest answer
which is to reformat the drive. A quick format might suffice since that
doesn't touch the file's sectors but just wipes the file system which
presumably would include the backup FAT. Otherwise, you're hunting
around for utilities that can modify the backup FAT or force it to sync
with the primary FAT, checking if synchronization has been disabled in
the boot sector, and more super-geek manipulations.

glee wrote:
"Bill in Co" wrote in message
m...
glee wrote:
"Bill in Co" wrote in message
m...
Bruce Hagen wrote:
"Bill in Co" wrote in message
...
Has anyone come across a program that quick erases a USB flash
drive
stick, so that a simple unerase program doesn't show what files
were on
it? (I don't do this for security reasons, I only do it for my own
convenience (when I'm trying to recall what changes I make on the
drive subsequentially; it's hard to explain :-).

So here is what I have discovered:
"Eraser" doesn't seem to be able to do it for flash drives,

Correction: some flash drives, at least. It seems to depend on the specific
instances.

although it
works well on other drives. (I'm just talking about using the
basic erase options here)

The WinXP disk defragger(s) don't do it, either.

BUT the standard Win98/ME defragger DOES do it! And you only have to
run it for a few seconds to clear traces of any file entries; it
doesn't need to run to completion.

Clearly the Win98/ME defrag works a lot better in that one regard
(on
FAT volumes) than the WinXP defragger(s) do. It somehow erases
the FAT table entries, where the Win XP defraggers don't.



Unless I'm missing your point, plug in the flash drive, right click
on the drive letter and format it.

OK, my bad, I didn't explain it correctly.

I want to do this on flash drives that already have data that I wish
to preserve. Let me explain:

I have some USB flash drives where I might decide to add some files,
then later delete them, and want it to look as if I hadn't added them
(i.e. a clean slate) for the next experiment. And the way I check
that is: to run an unerase program to see what was left there, and
what's not, and what I've just recently erased . To do this, I need
the drive to appear to be cleaned (of those entries) before the next
test. I guess I'm having a hard time explaining this. :-)

So, what happens when you try to do it with Eraser? Does it fail
with an error message? Does it hang? Does it complete as if it has
succeeded but the undelete program still sees the files?

Eraser runs fine, but it just doesn't remove the file list.
I use the erase (overwrite) unused space directory entries option,
which works great, EXCEPT on flash drives. It's very fast and works
great on most disks. (I'm not trying to go through and erase all
remnants (i.e. for security reasons), which is a completely different
scenario -just the directory entries.

IIRC, there was actually a note on their web site (and some other
sites) that admits this is a difficult task to accomplish with flash
drives, due to their wear leveling routines (moving the stored
"locations" around after each rewrite for wear leveling).


I don't think an undelete program will show you files that are
recoverable if all it sees is the index, the list... but not the data

Wait - nobody said anything about files that are recoverable. That wasn't
my desire, anyways :-) Actually, the unerase programs typically show
files that were erased and whether or not they've been overwritten
(clusters), so you can get some idea of what your chances are in trying to
recover them successfully or not. (If some of the clusters have been
overwritten, the chances are slim, of course).

I've been using "Recuva" (a nice freebie unerase/undelete program) for most
of these checks). More below.

itself that can be recovered. What I'm saying is, you are trying to get
Eraser to just delete the file list.... that's not what is does, as I
recall, it overwrites the actual data on disk. If you still see the
file listed by the undeleter, then the data itself is still available.

It sounds like you only want to delete the file list of names but not
the data itself.... AFAIK Eraser doesn't do that in the first place.
Eraser was developed primarily to overwrite the data. Are you using
some other option in Eraser that purports to remove file names but not
overwrite the data? I don't see why Eraser would even have that option
since it is designed for security purposes to overwrite the actual data.

Yes, that's what I was doing. By running it with the option to simply
overwrite the directory entries, it essentially does that - wipes out the
directory entries, (but, as you said, if you wanted to, you could probably
still recover some file data, but that is not an issue for me). Anyways,
the option is indeed there. The advantage of this option is that it does a
"quick erase" of leftover directory entries, without formatting the disk and
wiping out everything on it - which I don't want. (And it also makes it
somewhat more difficult for an unerase program to successfully find and
restore data, since the directory entries were erased - I've been around the
block on that one, but that's another story :-).

The last time I used Eraser was over 10 years ago, so perhaps it
changed, but from the readme file of that version:

"Eraser is an advanced security tool, which allows you to completely
remove sensitive data from your hard drive by overwriting it several
times with carefully selected patterns..... The patterns used for
overwriting are based on Peter Gutmann's paper "Secure Deletion of Data
from Magnetic and Solid-State Memory" and they are selected to
effectively remove the magnetic remnants from the hard disk making it
impossible to recover the data. Other methods include the one defined
in the National Industrial Security Program Operating Manual of the US
Department of Defense and overwriting with pseudo-random data up to one
hundred times."

I don't see any mention of it having an option to remove files from the
list without overwriting the data. It sounds like it is just being
unsuccessful working on your flash memory for other reasons.

Well, see above. Thanks for the info. And btw, most of the time it works
pretty well in that capacity - it's just a small issue for me for some
drives. :-)

VanguardLH wrote:
The default file system for removable media is FAT. There are 2 copies
of the FAT (file allocation table) to provide redundancy checking. That
an old entry is in the duplicate FAT shouldn't be seen by normal apps -
but then you're not using a normal app as it is not just issuing system
API calls regarding FAT entries but actually digging into the FAT at a
low-level to go look in the duplicate and unused copy.

The 2 copies of the FAT are tightly synchronized on writes to ensure
they have equal allocations of which clusters belong to which file.
However, on reads, the 2nd copy is only used when error occur in the 1st
FAT copy. The 2nd copy is so infrequently used that it might as well as
not exist. Even disk repair tools don't use the 2nd FAT.

Normally there are 2 copies of the FAT but a boot sector (byte 16) can
specify the number of copies (1 or 2; default is 2). See
http://www.win.tue.nl/~aeb/linux/fs/fat/fat-1.html, section 1.2, Boot
Sector. For FAT12 or FAT16, only the first or primary FAT gets used and
the 2nd is ignored but kept in sync. For FAT32, you could select which
copy was the primary FAT. That meant you could switch between FATs if
one got corrupt by changing a 4-bit value within the Flags field (never
had to do that so I don't of any handy tools for switching between
primary and backup FATs under FAT32). Other than a disk editor (where
you can look at and edit any sector on the disk), I didn't bother
searching around for tools that would let the user configure whether or
not there was the 2nd or duplicate FAT copy. When you delete a file,
its entry is removed from the primary FAT copy. I would've expected the
2nd copy to get updated, too, but apparently not in your case. Since
you are writing to the primary FAT when removing a file's entry there,
the write operation should mandate a synchronization of the backup FAT.
For some reason, perhaps your FAT copies are getting out of sync.

While I remember from long ago in my MS-DOS days that the 2nd FAT could
be used to replace the 1st FAT if the 1st FAT got corrupted, I never had
to do that. So I don't know of any tools that replace the 1st FAT with
the 2nd FAT. There is mention of using a hex editor to manually sync
(http://www.microswamp.com/index.php?...s/article&rn=3)
the 1st FAT from entries in the backup FAT so I imagine there are tools
that will automatically overwrite the 1st FAT with the contents of the
backup FAT.

There is some info at http://averstak.tripod.com/fatdox/bootsec.htm
about the boot sector entries that affect behavior of the FAT. Search
on "sync" and note the article mentions that a flag can be used to
determine if the 2 FATs are kept in sync or not, how it is normally
unset (zeroed) but that disk tools might set it to fix problems;
however, if the bit remained set then subsequent synchronization won't
occur and the FATs will get out of sync. I suppose it's even possible
for tweaking every ounce of performance out of the device that the
manufacturer could disable synchronization to eliminate the overhead of
having to update 2 copies of the FAT during writes to the primary one.
I've seen some articles talking about disk utilities or low-level
commands (that bypass the system API) where they can exit with or
without synchronizing the FATs.

So it looks like your unerase utility is finding old entries in the 2nd
copy of the FAT for files that no longer exist either because you
deleted them or even after wiping free space to completely eradicate the
*file* contents.

No, I don't think this is it. But see my note to Glen where I explained it
better. The *option* I'm using with the Eraser program is under the unused
disk space tab, and it's simply to overwrite directory entries, which
normally does a pretty good and quick job of that (while leaving desired
data intact on the drive).

As has been mentioned, formatting will wipe the drive
and leave you with an empty FAT, including the 2nd one. Maybe even a
quick format would create new FATs (primary and backup) since you
already did the free space wipe.

So it looks like the first respondent, Bruce, had the easiest answer
which is to reformat the drive. A quick format might suffice since that
doesn't touch the file's sectors but just wipes the file system which
presumably would include the backup FAT. Otherwise, you're hunting
around for utilities that can modify the backup FAT or force it to sync
with the primary FAT, checking if synchronization has been disabled in
the boot sector, and more super-geek manipulations.

"Bill in Co" wrote in message ...
Has anyone come across a program that quick erases a USB flash drive stick,
so that a simple unerase program doesn't show what files were on it? (I
don't do this for security reasons, I only do it for my own convenience
(when I'm trying to recall what changes I make on the drive subsequentially;
it's hard to explain :-).

So here is what I have discovered:
"Eraser" doesn't seem to be able to do it for flash dirves, although it
works well on other drives. (I'm just talking about using the basic erase
options here)

The WinXP disk defragger(s) don't do it, either.

BUT the standard Win98/ME defragger DOES do it! And you only have to run it
for a few seconds to clear traces of any file entries; it doesn't need to
run to completion.

Clearly the Win98/ME defrag works a lot better in that one regard (on FAT
volumes) than the WinXP defragger(s) do. It somehow erases the FAT table
entries, where the Win XP defraggers don't.



Win98/ME works Eraser;
because the USB flash drive stick is FAT32 volumes..

000-222-000 wrote:
"Bill in Co" wrote in message
...
Has anyone come across a program that quick erases a USB flash drive
stick,
so that a simple unerase program doesn't show what files were on it? (I
don't do this for security reasons, I only do it for my own convenience
(when I'm trying to recall what changes I make on the drive
subsequentially;
it's hard to explain :-).

So here is what I have discovered:
"Eraser" doesn't seem to be able to do it for flash dirves, although it
works well on other drives. (I'm just talking about using the basic
erase
options here)

The WinXP disk defragger(s) don't do it, either.

BUT the standard Win98/ME defragger DOES do it! And you only have to run
it
for a few seconds to clear traces of any file entries; it doesn't need to
run to completion.

Clearly the Win98/ME defrag works a lot better in that one regard (on FAT
volumes) than the WinXP defragger(s) do. It somehow erases the FAT
table
entries, where the Win XP defraggers don't.



Win98/ME works [like] Eraser;
because the USB flash drive stick is FAT32 volumes..

Yes, but that doesn't explain why the WinXP defragger doesn't do it when it
is defragging a FAT32 volume, while the Win98/ME one does:

Both the regular Win98/ME defragger AND the the regular WinXP defragger can
defrag FAT32 volumes, but only the former (the Win98/ME one) seems to erase
any previously erased file table entries (that can be discovered by running
an unerase program).

And the defragger doesn't even have to run to completion to do that (just
briefly start it, and then stop it a couple of seconds later, and that's
done).

(most of the *files* themselves would be unrecoverable since some of their
clusters have likely been reused, but that's not the issue here)

"Bill in Co" wrote in message
m...
000-222-000 wrote:
"Bill in Co" wrote in message
...
Has anyone come across a program that quick erases a USB flash drive
stick,
so that a simple unerase program doesn't show what files were on it?
(I
don't do this for security reasons, I only do it for my own
convenience
(when I'm trying to recall what changes I make on the drive
subsequentially;
it's hard to explain :-).

So here is what I have discovered:
"Eraser" doesn't seem to be able to do it for flash dirves, although
it
works well on other drives. (I'm just talking about using the basic
erase
options here)

The WinXP disk defragger(s) don't do it, either.

BUT the standard Win98/ME defragger DOES do it! And you only have
to run it
for a few seconds to clear traces of any file entries; it doesn't
need to
run to completion.

Clearly the Win98/ME defrag works a lot better in that one regard
(on FAT
volumes) than the WinXP defragger(s) do. It somehow erases the FAT
table
entries, where the Win XP defraggers don't.



Win98/ME works [like] Eraser;
because the USB flash drive stick is FAT32 volumes..

Yes, but that doesn't explain why the WinXP defragger doesn't do it
when it is defragging a FAT32 volume, while the Win98/ME one does:

Both the regular Win98/ME defragger AND the the regular WinXP
defragger can defrag FAT32 volumes, but only the former (the Win98/ME
one) seems to erase any previously erased file table entries (that can
be discovered by running an unerase program).

And the defragger doesn't even have to run to completion to do that
(just briefly start it, and then stop it a couple of seconds later,
and that's done).

(most of the *files* themselves would be unrecoverable since some of
their clusters have likely been reused, but that's not the issue here)


OK, apparently I misunderstood your original question/issue what you
were doing with the files and what you were trying to achieve.

In regard to the difference in what Win98 defrag does compared to WinXP
defrag, defrag programs by different companies work differently, use
different algorithms for defragging, and some do a more "complete" job
than others based on what the makers decide is optimal.

The Win98 defragger was made by Symantec, and the WinXP defragger is a
stripped-down version of Executive Software's Diskeeper. They work in
different ways, as you can see.
--
Glen Ventura
MS MVP Oct. 2002 - Sept. 2009
CompTIA A+