General discussion

External USB laptop hard drive storage file corruption

Feb 2, 2007 6:14AM PST

I have an irritating issue with the above (hardware listed below) which is used as a backup/archive.

When I copy files - photos, music, apps - to the drive I find that some files have become corrupted. There is no error message, nor are errors found with various disk-checking utilities. I only realise when I open a photo (an eg bottom half will have colour shifted), music (will skip at some point before end of track) or an app (will just warn is corrupted).

The same errors do not occur when I make a similar transfer of files to external USB stick/SD cards (same machine, files, port).

I have tried Chkdsk, formats, partitions in their fullest forms. Nothing wrong. I have tried Norton Disk Doctor, Seagate Seatools (their own disk-checking utility) etc. No problems according to them.

When I copy back the files to the hard drive on the original machine, they are still corrupted.

Alas I do not have a machine that supports external USB drives at start-up so Seagate's own boot level disk utility has not been an option so far. Maybe a zero fill or low-level format is a sensible next option?

I must confess I do not know the process by which data is transferred, written and verified however it seems to be a problem with data being written?

I'd welcome any thoughts and/or answers as it has become very frustrating. Obviously if I cannot trust the integrity of data being backup up then I cannot use the device. I would, at the very least, wish to pinpoint the source of evil - hard drive fault or enclosure..not knowing is half the frustration.


Generic USB2.0 external enclosure with Seagate Momentus 40GB 2.5in drive 5400RPM 8MB cache
Various PCs all running XP Pro SP2, up-to-date, clean, USB2.0
Mostly used with Sony Z1XSP, 1.7 Centrino, 1GB/80GB

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Let's try the usual. Is the volume in FAT32?
Feb 2, 2007 9:32AM PST

I can't count how many times that gets corrupted.


Also, try another USB 2.0 cable. Be sure it is such a cable.

Is this drive USB powered? Try a powered USB hub rather than the laptop USB power as source.


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Feb 2, 2007 4:19PM PST

Hi Bob - no it's NTFS although I have tried FAT32.

I've also had the same problem on a Dell Dimension desktop so I don't think it's a question of power.

I don't have a spare cable so I'll try and track one down - it's one of those miniUSB to USB cables with a second USB connector (I think for the purpose you have just mentioned - power).

I have no understanding of what exists or remains on a disk when re-formatted or the partition is removed. Is this where low-level formatting comes in - would it be worth trying?

I've read about some USB enclosures generating problems however normally they also generate error messages. My gut feeling is enclosure - cheap and probably made by a kid in asia - anything possible!

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Why did you dismiss power?
Feb 2, 2007 10:01PM PST

USB power is not assured so a powered HUB may be the cure. Try that.


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On the task list
Feb 2, 2007 10:26PM PST

Thanks Bob-both that and trying another cable will take some time as I do not readily have these to hand. So, points taken and not excluded - just deferred until possible!

In the meantime, any other knowledge or advice is welcome.

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Long shot. Acoustic setting.
Feb 2, 2007 11:42PM PST

To drop the possible power consumption as the head moves see if you can find the software tool for your hard disk and see if it allows you to lower the acoustic value. Why this could help. One power drain is when the head moves. At the lower acoustic setting the head would move a bit more slowly and could help if there was that hairy edge power issue.


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I'm back...
Feb 3, 2007 4:26AM PST

...major internet downtime here!

Re: acoustic. I have already used the Seagate Tools. They didn't offer that option. Incidentally all the drive self-tests came up clear of any errors or irregularities.

Re: files. Why would it be that certain files fail? For instance the AVG Free installer always corrupts whereas some other apps are fine. Out of hundreds of photos in numerous folders, it seems a certain few from a certain couple of folders corrupt (although not always the same photos, from the same folders).

They are fine until they reach external drive.

If it was not for the fact that AVG is freshly downloaded, I would be questioning the source file integrity.

Bob, I will still be trying your suggetions when I can however I cannot help but feel I also need to be asking what might make these certain files susceptible to corruption whilst others not?

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Think of whipping a rope.
Feb 3, 2007 7:07AM PST

This is a near physical analogy of the signal on the USB cable. If the USB cable is not perfect the signal could be distorted. If I recall you have a laptop so the usual front port issue we see in desktops is not at issue. That leaves me with USB power or cable issues.

I have this one USB powered drive that will corrupt if I don't use the cable that came with it. It took a little sleuthing but I found they bulked up on the power supply wires in that cable whereas some USB cables are cheap cheap and used very small wires.

All this is rather academic and hopefully you find a cure.


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Over and out
Feb 3, 2007 8:40AM PST

Bob, I will follow your advice and try to find a quality cable.

Very many thanks for your insight.

It may not be in the immediate future however I shall post the outcome here.

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External USB 2.5" Drive Corruption
Mar 23, 2007 5:09PM PDT

(Please excuse my errors in english )

Hi there - I've been reading this thread...

I cant help but I have some info - I've been battling with this kind of random corruption for a wile now - all involving self powered Drives (2.5") in external cases - running USB2...

We have used Maxtor / Hitatchi / Seagate drives -
and VANTEC as well as no name brand External casings ...

and the error persisted to varying degrees in all events ...

I know this SEEMS to be a power issue - but the vantec casings have support for power input supply - and even when power is given, the errors persist...

Furthermore older motherboards such as Socket A AMD don't seem to have this problem .. - only NEWER motherboard chipsets, AMD & Intel..

One "WorkAround" I Use is to put an ADDITIONAL USB2 ports Pci card into a system ...

When running the drive off a Standalone card, the drive errors reduce to almost None ... < 1 error in 40 GB of transfer (on average)

But this is STILL not good enough as corruption DOES still occur .. and you cant really add ports to a Mobile Pc...

Furthermore - analysing the corruption reveals that


In any of our test subjects (Patterned Parity & other direct sequense files generated spesificly for testing) Packets of data (of varying size) during the transfer seem to get "Shuffeled" around...

All data makes it to the drive - but certain groups of data are "out of order" ...

This voids the whole "Faulty cable" / "Poor power" and other such generic assumptions that people jump to...

The problem would seem to be more complex than this ...

Although beyond this - I'm still trying to discover...

This probably wont help much - but maby some of this info will lead to an answer - As I too battle regularly with this...

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If I had your isue I would.
Mar 23, 2007 9:10PM PDT

a. Use the USB PCI card connection.
b. Get SPINRITE and run it on said drive.
c. Run a compare after the copy.


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Generic cable solution worked for me
Jun 27, 2007 2:56AM PDT

Just thought I'd come back to this thread and say I have had absolutely no problems with using the same 2.5in drive (as well as others), and on the same USB ports, but with a generic 2.5/3.5in/SATA Cable.

On the other hand (or shut one case and another bursts in your face), I haven't been able to connect to a 3.5in drive though although that's probably to do with the drive being corrupted. Any thoughts on that are welcome at:

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Anyone else can confirm this?
Jan 31, 2008 3:26AM PST

Hi dougalzene,

Thank you for this try.
Anyone else can confirm that there is no corruptions on 2.5 USB2 SATA drive/enclosure?

Thank you,

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Generic 2.5/3.5in/SATA Cable
Jan 31, 2008 5:04AM PST

>same 2.5in drive (as well as others), and on the same USB ports, but with a generic 2.5/3.5in/SATA Cable

What is it - generic 2.5/3.5in/SATA Cable? Where to get this product?
Is it connects somehow 2.5 IDE to 2.5 SATA USB2 Enclosure?

Thank you

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Same problem but only with WinXP and not Win98 SE!!!
May 16, 2008 1:50AM PDT

I have the same problem with and 2.5 external HD. I do not have any problems with my 3.5 external HDs - this for many years.

My problem is as follows. I can copy data to the external disc without any corruption. But when I read it with WinXP (read/or copy or whatever read - even any CRC check) I get CRC errors - silent ones at different positions - I have to check to find them. The OS does not say anything.

But the write to the external disc is okay. If I use the same external disc with Win98 SE there is NO PROBLEM AT ALL - tested at the same computers. So Win98 SE does not have this problem at all. Because of Win98 I could verify that the file written by WinXP was okay. But never any read of WinXP from the external 2.5 HD. I have installed a clean WinXP SP3 - the same problem.

Since it works with Win98 SE at several computers problem free and even the write works at WinXP but not the read at WinXP it must be a problem in connection with WinXP - and I have SP3 already. It cannot be the power or the USB port.

The big danger is that people do not realize this error if they do not check for CRC errors. I found this out by accident when I used Acronis and made a check of a partition image.

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Tell me why this isn't a warranty issue.
May 16, 2008 1:54AM PDT

Given the severity of the issue why are these units not back at the store or repair shop?

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The hardware seems to be okay. WinXP seems to be the problem
May 16, 2008 2:15AM PDT

I never got any error with Win98 SE and I never got any error with WinXP at a write from the internal to the external 2.5 HD. Only when WinXP reads the data from the external 2.5 HD I got the problem. And if you copy the data you have written before with WinXP to the external HD with WinXP and delete the first write to the external HD you have lost.

So if you copy from your internal HD to your external HD with WinXP the data are still perfect. But if you copy back and delete the data from the external HD you have a problem. Of course all programs reading the data when using WinXP get the same data scrap - WinXP reads and gives it to them - the wrong data. And since it read wrong data it will write them at a copy.

You can only rescue your data back to the internal HD by using Win98 SE since it does not create data scrap when reading (and when writing). At least this is what I found out after searching for endless hours. It does not solve the problem with WinXP (even SP3) but it shows at least a way to rescue your data. At least this worked in my tests.

All this happened never with a 3.5 external HD and I have been using them for many years.

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I see you wrote XP 2 times.
May 16, 2008 2:19AM PDT

Are you aware that SP2 contained some USB 2.0 patches that we (painfully) discovered to matter on this issue?

I see you note SP3 but we haven't tried that. There is another issue here. Windows 98se would mean FAT32 which we found to be unreliable for any company use. Back to NTFS.

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SP2 and SP3 - no difference
May 16, 2008 2:30AM PDT

I checked both - SP2 and SP3 there is no difference at all - same problem. I could only check VIA chipsets. This with NTFS and Win98 SE is of course a problem. Linux worked great too. Acronis in CD mode uses Linux as far as I know and could verify & read the data without any problem - what it could not do within XP when I used Acronis. Perhaps this helps.

I really would like to solve this problem. I guess many have this without being aware of it. I had luck because I use Acronis and make always a verification of the backup. And this was one of the first things I did with this external HD.

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I predict no solution (ever.)
May 16, 2008 2:32AM PDT

Since Windows 98se is in the mix and that means FAT32 I predict no solution will ever be found for or from Microsoft on this one.

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Not so quick!
May 16, 2008 2:29PM PDT

I changed the external 2.5 disk to NTFS and there is no difference. Used different cluster sizes. No change. So this problem has nothing at all to do with Win98 or FAT32 or FAT16. It is simply a problem of WinXP.

Microsoft claims the rights for USB with their own drivers - not even VIA can change this. So THEY have to find a fix. A DOS (in the sense of Disk Operating System) that cannot handle data without errors/error messages is the worst thing that can happen. Want to have Vista - that protects Vista? I rather want to have a DOS that protects my data. The CRC errors without any error message are a shocking fact.

In respect of SP3 - it did not solve any problems but created new ones. Had to re-install programs with drivers like Acronis, Nero and many others after the update. Microsoft did not even check if the update works with such common software - hard to believe. There is no hint that you might get problems. What are all those people doing at this company...???

Will not switch to Vista - want to use my computer and not solve/fight problems created by Microsoft. Not even multi cores make much sense for most PC users. The CPUs even got slower for single core applications. So we might have reached a limit for a while.

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If you research this conversion you find
May 16, 2008 11:31PM PDT

There are issues in the FAT32 to NTFS conversion. The good news is that I can't duplicate your issue across 5 very different USB hard disks so I stopped trying to make this happen. At this point it's either failing hardware that only shows on your systems or that drive and it has an issue.

You could delete the partition, create it anew, format the drive and run something like SPINRITE to see if there are iffy areas on that drive. That would take a day of testing but after spending time on this with 5 drives I can't agree there is an issue with XP SP2 or Windows 2000 SP4. Sorry I didn't feel like trying Vista.

Sorry but I can't see the issue here. I've run into it but we change the drives to get it fixed.

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Same problem different answer
Aug 24, 2008 10:29PM PDT


Seems like a few people have had almost exactly the same problem that i have also experienced. Its very frustrating! Here is what it turned out to be in my case.

I have 2 identical USB2/Firewire external enclosures.
Each enclosure can (and is) powered by a dedicated power supply (so no power problems)

One enclosure has a 120GB IDE drive and the other a 160GB drive.

In my case i was running a dual boot linux/windows xp computer. I tried different format/files systems. Fat32, NTFS and EXT3. All same result under 2 different operating systems and 3 different file systems.

Most files copied fine to the drives, but some particular files would ALWAYS fail. Which gave a good repeatable test. Under both operating systems the corruption would occur silently, so the message coming back from the drive must be that everything is going ok.

The best way i found to test it was to do a file compare (for example using diff) or calculating a checksum on both the original and the copy such as md5sum.

At first I thought that the common thing was the drive enclosures.

So i tried a memory stick with the same file that always corrupted, and it corrupted upon a copy to the memory stick. Interestingly i thought that the i had tried the memory stick before but it turns out that the corruption happens only on three files in my entire backup so i just hadent copied that particular file to the memory stick before.

So that ruled out file system, operating system, drive encolsures and drives.

In my case i had a USB hub. I tried the memory stick straight into the computer and it worked, also the external drives also worked this way.

So for some reason out of thousands and thousands of files a couple of particular files always get corrupted when going through this particular USB hub, and even worse they corrupt silently and the only way to find out is by doing some sort of file compare or checksum.

Anyway thats how it turned out for me.

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