Problem unzipping files on external HD

[ggull]

Thanks for the possibilities you suggest --

Some guesses. Firewire cable defective in some manner.

As stated in original post, my experiments included using two different
cables, resulting in failure with both on the original computer. Using at
least one of these cables and the same drive on a second computer, the copy
was OK.
This seems to eliminate defective cable(s), no?
That's why I did the experiments reported in OP.

Hard drive's enclosure for firewire interface.

Again, experiments already reported seem to eliminate this. I had the
problem for two distinct external drives / enclosures. Both Acomdata, but
different capacities and models. (Three enclosures if you count the
original extraction experience.) Used on a second computer, no problem.

These and other experiments already done and reported are why I felt the
problem probably lies in the Gateway XP computer itself, not the cable or
external drive. Also something more fundamental than a dirty or loose
connector, since I tried all three ports on the Gateway.

Am using strictly firewire interface, Acomdata enclosure. Onboard
firewire is Texas Instruments chip for firewire (motherboard). Works
great in 98SE, ME, and XP SP1, and now, SP2.

An impressive array of upgrades for a single MB . And I'm glad to hear
your Acomdata drive has been running all that while.

I'm just curious -- would you have noticed write errors every 100 MB or so?
Do you use files that large, if it's a threshold thing? Are they something
that might just present a slight glitch (music or photos) instead of
outright croaking?

You might remake the enclosure's hard drive partition while connected via
firewire, not usb.

I'm not familiar with "remake the ... partition". Do you mean to format it?
Makes some kind of sense, but these came pre-formatted, and I'll bet the
format was done before they were put in the enclosures, so I'd think it's a
long shot. But again, this is focusing on the drive, not the onboard
firewire.

 

[Quaoar]

This thread started on microsoft.public.windowsxp.general, when I had
problems unzipping gigabyte size archives downloaded directly to an external
firewire hard drive. Pegasus suggested I compare a file downloaded to an
internal HD with that same file copied to the external HD using
and indeed that found differences, and also noted that the copy was shorter
than the original (though right-click > properties shows they are the same
"size"). Pegasus suggested I try a hardware group, so here I am.

I think the problem is more with the Firewire hw/sw on my computer than the
hard drives per se, but I hope you can give me some ideas or point me to a
more relevant group.

I have available multiple computers, external drives, and cables, and ran a
bunch of tests that seem to show it is a problem with Firewire only, on the
one computer only.
The computer in question is a Gateway 503GR, two internal SATA HDs, DVD, CD
drives, nothing else connected to the ports except a USB printer (lj 1012).
WinXP HE SP2, all relevant updates.

Here are the test -- skip to the end at any time --

Test 1) External HD #1 -- 160 GB Acomdata Dual Firewire/USB
FAILS
Firewire, cable 1, rear port on computer. Internal drive J:, external F:
Copy J:\SCRATCH\big.zip to F:\SCRATCH\big.zip
fc /b j:\.scratch\big.zip f:\scratch\big.zip
FC seems to be finding clumps of difference ... i.e. outputs a bunch of
lines, pauses, outputs more, pauses, etc. Maybe 5 or 10 clumps, dozens or
at most hundreds of lines each.
Total number of lines longer than buffer available in command prompt, but
here are last few

21343FFB: 00 15
21343FFC: B2 B7
21343FFD: FF 41
21343FFE: FF 8F
21343FFF: FF DD
FC: J:\SCRATCH\big.zip longer than F:\SCRATCH\BIG.ZIP

Test 2) Change cable and port.
FAILS
HD #1
Firewire, Cable 2, front port
Copy...
fc ...
Similar differences, but with different detail. This time no "longer than"
notice.

Test 3) Use USB connection: Note this is still same external HD: OK
HD # 1
USB, USB Cable 1, front USB port on computer.
File Compare output:

Comparing files J:\SCRATCH\big.zip and F:\SCRATCH\BIG.ZIP
FC: no differences encountered

Test 4) Try a different Firewire HD:
FAILS
HD # 2, 250 GB Acomdata Firewire -- Drive M:
Firewire, cable 1, rear port on computer
Copy...
fc ...
Similar behavior, several patches of difference.

Test 5) Transfer the file big.zip to a second computer using DVD-RW.
OK
This is a WIndows Me machine with Firewire but only USB1 Copied to HD#2
and ran FC -- no differences found.

If it matters the file system on the Gateway (XP) is NTFS, and on the Me
machine and the external drives, FAT32.

SO ...

1) Am I correct in thinking this indicates a problem with Firewire on the
Gateway?

2) How can I narrow it down further (eg hardware / software) and then fix
it?

3) Lastly, why doesn't the system notice the bad write when copying to the
external HD? I thought that data files (as opposed to audio CD files) had a
bunch of built-in error detection and correction.

In all of this you don't mention if the external drive is DC powered or
if you use only FW port power? I have seen this type of behavior on
large files with a low-power notebook drive using single-port USB. With
double-port USB or 5volt DC power there is no problem with this drive.
I don't have any powered FW ports (notebooks only) so I've not had any
opportunity to run on FW port power.

WRT your comment about the system checking CRC on the copied files, I
never had any notice of file corruption - in fact in one early session,
the entire disk structure became corrupt without any OS intervention.

Q