Very strange... bad sectors but can still copy??

Soldato
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Hey guys/gals,

So I have an old Western Digital 2TB drive which appears to be on its way out. All the signs, along with the scans I've managed to run on it, tell me it has bad sectors, but what intrigues me is that I am still able to pull files from it!... It just takes forever to do so. When it hits a bad spot it crawls down to like 200 KB/sec.

The files I am copying are quite large (video files, roughly 10GB each), and it's as if it slowly works its way through the "damaged fragments" and every now and then leaps forward at normal speed until it hits another damaged fragment. It's somewhat reassuring because despite the slowness it does make progress eventually, rather than timing out or dying altogether!

The question is, if I never get a "file could not be read" error, and the hard drive just slows to a crawl when I hit bad patches, does this mean there is still hope for the drive? How is it possible I can pull data without some form of fatal error, if the surface is damaged? :confused:


I ran a scan on it with HDTune, which despite being a "quick" scan (usually takes about 1 minute), took over 10 hours, as it absolutely crawled each time it hit a red block:

VObZAhL.png



When I've pulled the last file off it, I'll be writing zeros to it and doing another scan to see if it chokes at any point.

So what do you reckon ladies / gents... do I have a new paperweight or not? :D
 
Have you tried running an advanced windows chkdsk on it, select scan for and attempt to recover bad sectors, takes a while to run but it maybe bad sectors as in corruption, rather than surface damage.
 
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Basically, the drive will make multiple attempts at reading the 'damaged' sector.
If it can't determine reliably the contents of said sector, you will then get the file cannot be read error.

Paperweight.

-Leezer-
 
Have you tried running an advanced windows chkdsk on it, select scan for and attempt to recover bad sectors, takes a while to run but it maybe bad sectors as in corruption, rather than surface damage.
Not windows, but I ran the Advanced scan with the Western Digital Lifeguard tool. I kid you not, it took like a week to complete. In the end, all it said was "Test failed. Too many bad sectors", which I knew already.

Basically, the drive will make multiple attempts at reading the 'damaged' sector.
If it can't determine reliably the contents of said sector, you will then get the file cannot be read error.

Paperweight.

-Leezer-
Well this is the thing, it manages to grab the file successfully, it just takes several hours :D I have yet to see a single "file cannot be read" error.

...

It's almost as if the controller part of the hard drive is what's getting stuck. It fails to process any commands (e.g. browsing directories) if its busy waiting for a read attempt to complete.
 
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I recently had the same thing with a Toshiba drive which has now gone for RMA. Whatever the issue, it is not normal. Get your data off it while you still can and get a replacement.
 
I'm recovering the remaining files, only 6 remaining but it's slow.

Testing the copied files now. Most are OK.. but I've found some faulty ones. For 3 of the corrupt ones, below is what the corruptions on the files look like:

SDPqaSn.png


The corruptions come in gaps at regular intervals which I think is pretty interesting... what do you guys think? :)


The HDD is out of warranty so can't really do much with it. I've already started a new project for data storage (rackmount expandable disk enclosure array) so replacing it isn't the problem. Just seems a waste to throw it away a 2TB drive if I can rescue it :)

postmanfw once the data is recovered I'll look into hddregenerator, cheers for the suggestion
 
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I know what you mean about not wanting to bin it, but even if you managed to get it working again, could you ever trust it with anything worth storing?
Short answer: of course not :p

Writing zeros to it as we speak. Will then do some surface tests etc and see how it fares. I guess this is more of an experiment at this point rather than anything else :)
 
i tried hdd regen a while ago but all the areas it "recovered" ended up failing again within months. I have had some success with partitioning drives so that the bad areas are left unpartitioned, but only when its had a couple of bad sectors, nothing as bad as the one shown here :P
 
With hdd regen if it finds bad sectors then thats it really....only use it myself to test drives and get them working enough to be able to recover data from them.

Another i forgot top mention is spinrite but that can take a very long time to work its magic for emergency data recovery...but worth it of course if it gets job done.
 
HDD regen failed during the quick scan, after a point it just got stuck and recommended I abort.

Tried writing zeros to it with the Western Digital Data LifeGuard tool, left it for like 4 days... got to about 90% and it got permanently stuck. I thought that this, of all things, might have succeeded as the majority of my bad sectors were around the 30-45% mark.

The warranty ran out in September 2013 :( And I already made sure to refresh warranty period to reflect purchase date.

So yeah.... the thing is definitely a paper weight... Oh well :o
 
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