WHY my files on external drive got corrupted?? HELP!!!!

[albertlee]

Hello all

 

Now I have a very serious problem........

 

 

I am now using an external harddrive to save all my files, as some of you might know that long time ago I got a serious OS corruption.

 

As usual, 1 of the directories in the external drive was working properly, but today, when I tried to open it... I got this message in a dialogue box:

"Cannot access X:\xxx. File or directory is corrupted and unreadable"

 

Any help???

[5614]

Try running check disk.

 

my computer > right click on drive > properties > tools > check now > tick both boxes > start > you'll need to reboot

 

Try that... I'm assuming you have winXP.

[1veedo]

I guess you're not experienced w/ unix, but I know most of the time, live CDs are able to read data that looks corrupt to Windows. Most data recovery "experts" will do this if Windows wont boot..they just copy all the folders that looks like it has user-put files to a temporary location, reinstall Windows, and put them back. Everything works. (I actually did this for my teacher's laptop recently. Something went bad w/ the NTFS partition and required a full format. Booted knopix and look, there's hda1. Bingo!)

 

Of course, this isn't your situation, but I'm sure you can find some applications that will 'recover' everything from that drive. You don't even need a liveCD; just something smarter then Windows to backup your data before you fix the HD.

 

And then there's the worst case scenario...the HD itself is bad.

[albertlee]

ok, so...

 

can you recommand any small linux or unix OS specialized for restoring corrupted files under WinXP???

 

because since I am not expertise in Unix/Linux, I dont know the most capable one...

 

btw, why on earth Microsoft Windows itself isn't capable of restoring files under its own NTFS format???

 

My external harddrive's brand is HITATCHI, and I bought it origininally as a normal HD, then I put it in an USB device which can be used as an external drive altogether, does that have any influence at all??? because I have never encountered this sort of problem accessing local HD.....

 

 

Too bad, is it possible to retreive data from a formatted HD??, because I used to have a partition with my older XP, but it got corrputed, ie, unbootable, so I was too hasty to format (I thought it was the end of my files), I still have that partition, but just been formated, is it possible to get data back???

 

thanks for responds

 

Albert

[5614]

Yes, but it depends and you'll need a special program... if you have written over the data it is effectively impossible to recover, but if you have partitioned and not written over look on google for 'file recovery program':

http://www.google.co.uk/search?hl=en&q=file+recovery+program&meta=

or something like that, I've never used them but have heard a bit about em.

[albertlee]

5614, what do you mean by "written over" here???

[Dave]

When you delete a file, that file is not actually physically removed from the drive. Rather, the data blocks it occupied are marked as not in use - the data is still there, but the drive doesn't really care. It just knows that piece of the drive is available for writing. Then when you do some kind of write operation (copying a file for example), the drive will just overwrite those pieces when it gets to them.

 

The "undelete" type programs will basically scan the empty sectors of the disc in order to find any files (or file fragments) that can then be restored. However, the chances of undeleting the files will decrease rather rapidly depending upon how much time has passed. If you leave the drive for longer, chances are that it would probably be overwritten. It also depends to a certain extent on how big your drive is.

 

Added to this is the fact you've reformatted. If you chose the "quick format" option, then you might stand a chance. However, a "low-level" format will erase all of the data from the drive before it puts a filesystem/partition table on there, so you won't stand a chance of getting anything back from the drive. However, because you've reformatted, you probably won't get anything back from the drive now anyway. You can always try

 

Good luck.

[albertlee]

 

I did low-level formatting on my HD....

 

 

The other guys just didnot mention the idea of file recovery program when I mentioned that my Xp got corrupted in another thread, otherwise I could not have done formatting my whole HD, which has my academic reports and essays since 2 years.....>_<

 

any way, I will try...

 

Lastly, why external harddrive would encounter the problem like I mentioned?? is it the problem of the OS itself (xp), or the usage?

[Dave]

I wouldn't know to be honest - it could be a number of things:

 

1) The hard drive is failing is one option and probably the most likely. If it starts to make strange noises, you might have a problem.

2) There's some kind of problem with the caddy that the harddrive is housed in (USB/Firewire might be on the blink, power supply up the shoot, etc).

3) Some kind of filesystem problem; quite unlikely since NTFS is usually pretty good and pretty much rock solid.

4) Your motherboard might have a problem. Unlikely at best.

5) OS/software issues: You might have some kind of malicious software on there. Something might be borked somewhere. I don't really know

 

My suggestion is to take it out and test it on another computer. If you're still getting the same kind of problems, you can pretty much rule out everything except hardware failure. If this is the case, then try and get as much data off of it as you can and get it replaced. If the data is very important, then you might want to take it to a professional firm/data recovery place and see if they can get it off for you.

[1veedo]

Added to this is the fact you've reformatted. If you chose the "quick format" option, then you might stand a chance. However, a "low-level" format will erase all of the data from the drive before it puts a filesystem/partition table on there, so you won't stand a chance of getting anything back from the drive

Even if you do change the filling system, the data is still there. I've never recovered data from a formated drive, but I suspect you can tell the software that the data it's looking for was originally on NTFS or whatever.

 

The ONLY way to permanently erase data is to overwrite it. Things like deepdelete actually go over the drive complete and write over and over again to it.

 

And even after that, profesional recovery companies (that charge thousands of dollars) can set there w/ a microscope and examine the different layers (assuming, of coruse, that it's the right kind of HD).

 

albertlee, you obviously know that you did nor format the drive. The thread just got a little off track. Dave outlined soem things that may be getting in the way, but most likely it's just that windows (or the software reading your drive) is stupid. A lof of windows media players (like BSPlayer, and of course the default) will not load "corrupt" video although xine on Linux will.

 

It'd actually be easier if we had more info. Is your drive browsable? If it is, then it's most likely an application trying to read the data. Chances are that the app is bad. Can you open any file at all? If so, then it again, points to jsut that specific file. Maybe it was meant to be played by an "outdated" version fo whatever you're trying to view it w/. M$ wants you to upgrade! If that's the case, you can open all your files in OpenOffice, Apiword, or whatever and even save it to the "new" file type.

 

I'm assuming it's the entire drive, though. dave is correct in saying it's "rock solid," but when NTFS goes bad it doesn't take long for the entire drive to seem corrupt by windows. Normally when an NTFS goes, it's the entire drive and not just a chunk of bad sector (although those are a thing of the past too). I'm not entirely sure why Linux can read NTFS that Windows cant. It might be because Linux doesnt have restrictions on files placed on the upermost layer (where the database tables for NTFS and FAT are). Each Windows file system has a file allocation table which is equivalent to a superblock except w/o redundancy protection that keeps most filling systems running longer then NTFS (ext has multiple copies of the superblock and writes in a way to prevent fragmentation). On the top side, NTFS has encryption, compression, and security ACLs.

 

If you want your data, just try downloading a couple of file-explorers. The default windows "my computer" might have an issue about something. I know from experience that "corupt" partitions can generally be read by Linux. Like I said, that's how a lot of data recovery "experts" get your files back. You can try Knoppix, Ubuntu-Live, or just about any other Live CD. However, a word of warning, Linux cannot write to NTFS; well, it can in certain parameters, but NTFS can be screwed up completely by writing to it...NTFS can use journalling but defaultly doesnt. (dont worry, it wont let you write to it anyway). My point is that if you have no ware to put your data (no FAT, ext, or filling systems set up that Linux supports), you'd only be able to read the data and not move it somewhere else to backup your data. Maybe if you can find an HD laying around...plug it in and let Linux format it as FAT. Just copy your files over to and bingo! Reboot and hopefully windows wont complain anymore. After you see that your files are back, do whatever you have to w. your external drive and move your fiels back.

[albertlee]

 

I guess I should check the drive quick, because I had like what it is now for a long time, and I have used it as a P2P downloading drive.....

 

I hope the data have not been over written...

[albertlee]

By the way, the software I am using right now is GetDataBack, which I managed to retrieve data, but the data arent situated in their original directory, instead it situates in, for example, directory like 001E0A, or 002766.... and so on

 

Any way, what is the best way for you guys to back up your data????

[Dave]

The ONLY way to permanently erase data is to overwrite it.

 

This is what a low-level format does; it's also the reason why they take so long. Also called a zero-fill format, because it zero-fills the drive.

 

And even after that, profesional recovery companies (that charge thousands of dollars) can set there w/ a microscope and examine the different layers (assuming, of coruse, that it's the right kind of HD).

 

If you really want to format a drive, you do multiple passes overwriting the data with randomized bits - I believe there's a free utility out there for windows called Eraser.

[albertlee]

you are right, Dave...

 

after I formatted the drive, GetDataBack found no files at all from the state before I formatted.

[1veedo]

Whoa You actually formatted it? I thought your files were just "corrupt"!

I guess I should check the drive quick, because I had like what it is now for a long time, and I have used it as a P2P downloading drive.....

Geeze, P2P isn't that safe on something like WIndows! And yes, most of your data is probably overwritten. Sry, dude. Another way to loose data after a format is if your internet browser uses the partiton. I'm affraid P2P (if you're downloading alot) is even worse then that...

 

You might want to shut it down until you get as much data back as you can. There are programs that will retrieve from formated drives, and I guess you've found one.

 

I feel sorry for you. That has to suck.