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Monday, August 23, 2010

Kingston flash memory failure

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I know of one circumstance where any Windows XP machine will fail to recognize a flash drive. This may or may not be your problem. Some iterations of Windows OS require portable drives to be stopped and ejected via the 'safely remove hardware' wizard before any data is actually written to them. When data is copied onto the portable media in this situation, Windows will show that it has been copied, but will actually keep a log of the intended data transfer without carrying it out (Windows XP uses a delayed-write cache to speed up programs). When a user 'properly' removes a portable drive through the remove hardware dialog, the logged data transfer will be actually performed and the files transferred to the device and then Windows tells itself that the drive is not connected. Finally, it tells you that the flash drive can now be removed.
Almost all flash memory devices use some form of 'hot pluggable' interface to connect them with the various electronic devices they support. Hot pluggable means that the memory can be attached and removed from a powered-on device without fear of damage or hardware failure. USB is the most obvious example of this technology, and one that we are all familiar with. The one problem with this type of interface is the sense of invulnerability it engenders in the user. We become so accustomed to inserting and removing our flash memory devices at will that we often forget to make sure that all data transfer tasks have stopped first.
Trouble arises when users simply yank the USB media out of the computer without using the safely remove hardware option. There is no surer way to mess up a portable storage device than to yank it out of its socket when it is halfway through an operation. If you just pull the flash drive out without doing the Safely Remove Hardware step, you may lose the data that you thought was already written to the flash drive. Also, Windows won't properly turn off its internal settings for the drive. That means, if you insert the drive again, Windows XP won't recognize it.
Also Check in Disk Management and try to "assign" a drive letter
It is also possible you're plugging this drive into a USB hub?
Try plugging it in directly to one of the USB ports in the back of your computer.
Drivers shouldn't be an issue as XP uses a generic USB mass storage driver which works with pretty much all thumb drive (and most external hard drive) chipsets.
If there's nothing important on the thumb drive, you can try repartitioning and formatting the drive. It doesn't make sense it would work in one Windows XP and not the other, but I've seen it happen.
Try this: Start -- Run -- diskmgmt.msc
CAUTION: Do not alter any other drives. ONLY your thumb drives!
Find your thumb drive in the lower pane of the window, right click on the coloured partition blocks and triple check to make sure it is your thumb drive before continuing. Proceed to delete your thumb drive's partition(s).
Right click in the empty space of your thumb drive and create a new partition. Right click and format it in FAT or FAT32. It should work. And if you don't see your thumb drive listed, then something is wrong at the driver/hardware level.
Flash memory has a finite lifespan measured in erase and write cycles. That is to say, a specific block of NAND memory can only be written to and erased x number of times before it fails to reliably store data. In modern flash devices, this number generally extends to millions of operations, and longevity is further ensured by an algorithm built into the supporting circuitry of the memory that forces data to be written evenly across the available memory blocks, preventing one area of memory from becoming more 'worn' and failing faster. Supplementing this is another system which ensures that 'worn' sectors are mapped out of the grid of available memory, similar to the method used to deal with bad sectors in hard disk drives.
Flash memory can and does wear out though. While a typical USB drive or memory card should last years or decades of typical use, exposing flash media to more read-write intensive operations like running an operating system or hosting applications will cause premature wear and tear and the eventual failure of the device. So never defragment these drives, by defragging, you will wear them out faster.
I have been using my USB flash drives / hard drives for years and only one has stop working and that was a hard drive not a flash drive. I think it is extremely rare that three thumb drivers will go “bad” simultaneously. This suggests that there may be a problem with the way you are using them or in the environment you are using these drives. Also check that the USB extension wires that you are using are fine or not. You could also be a victim of a bad lot or fake copies of the drives. You didn’t mention whether you bought them together and from the same store or not. I bought a Kingston or what I thought was a Kingston 16 GB DataTraveler it turned out to be fake.
As for the data recovery is concerned you can go in for a professional help if the data is critical or opt for data recovery software which may or may not work in your case. While attempting recovery of data from a corrupted drive, your success here will vary depending on what exactly is wrong with the flash memory device in question. If the file system has been scrambled due to some devices performing an unexpected action or not reading the drive correctly, you may well be able to recover your data using special data recovery software.
On the other hand, if your device is failing due to physical damage or wear and tear, data recovery depends entirely on what part of the flash memory is damaged. One positive is that, unlike hard drives, flash devices have no moving parts and thus do not generally fall victim to the 'snowball' damage effect, where data recovery efforts on a faulty drive inflict more damage on it even as they rescue some of the data.
Hope this helps in solving some confusion on dead flash drives
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Market flooded by fakes!

I've been reading several pages of replies here and haven't seen mention of the fact that loads of people(including myself)have found that they are in posession of a "fake" Chinese made drive. These flash drives are being packaged and labeled as both name brand and generic, high-capacity storage drives, ranging from 8gb up to 32gb. In reality they are much, much less. My 8 gb generic turned out to be only 1gb. 
So after tackling operability issues by using the advice seen posted in the previous replies, hopefully you've got your drive working again. Data recovery is probably your chief concern at this point. If you still cant get your drive working, hang with me as some of the utilities/links I'll provide below might sort you out. I didnt actually opt for data recovery as I was resigned to the fact that I would start from scratch and just erased all my data. If you're having "issues" with your data, chances are that you've exceeded your actual storage limit and that your data is long gone already. As far as data recovery goes though, I've found that one of the best free programs is 
http://www.pcinspector.de/ 
The 2nd step then, is to find out just exactly how much storage space is available on your drive. You can do this using several utilities that I will provide links to, but Ive found that the best method is to use this home-made program found here: myblog.bloggybloggy.com/hacked-usb-key-2008/ 
It is a VERY simple program that writes .bmp images to your usb drive one at a time. While using the "view files as thumbnails" you can see at which point the test .bmp images become corrupt and thereby identify your full storage capacity. Just follow the instructions provided at the link. 
Another good program to evaluate your storage capacity is called Hdtach. It is available for free here:
The results are displayed as a line on a graph, which happens to spike upward at full capacity level. Again, quite easy to use.
Now that you've found your drive's true capacity you'll need to reset it as such, and perform a low-level format. Below you will find links to several great free utilities that are used for doing both:
Don't worry about the brand of your internal parts, but just follow step one and use the PD.exe utility as explained. 
If this doesnt work for you, then there are also 4 other programs/utilities available through this guy's blog. Two of which are the iformat.exe and iformat2.exe and are seen as posted as a reply so you must scroll down the page. The iformat2 program is posted as an .rar file so some of you might have issues converting from the .rar format, so here is a link to it in a traditional .zip format 
It is found at the end of the small article as is another helpful tool called usbview.exe which helps to identify the usb manufacturer. Not only have the usb sizes been "faked", but the chips as well. 
The 2 other tools for low-level formating and resizing/relabeling are called MP tools and are found here: 
myblog.bloggybloggy.com/usb-key-fix-mptools-11-05-2008/ 
myblog.bloggybloggy.com/fixing-hacked-usb-memstick2008/
Lasly, a really great stand alone low-level formatting tool is found here:  
hddguru.com/.../2006.04.12-HDD-Low-Level-Format-Tool/
I wanted to mention that there are 2 other tools available that worked for me, but identified my drive falsely as a 4gb. One is the microsoft flash drive manager utility found here: 
microsoft.com/..=94991901-bfc4-485e-bcae-c9df0accdaae
The other being the HP usb boot utility found here: 
See also the Portfree Production Program 3.27 relabelling/reformatting tool found in several versions from the poster named "winbinar" at this very useful forum's link: 
everythingusb.com/forums/showthread.php?threadid=5442
Wether or not you're dealing with a "faked" flash drive, I think that these utilities should provide you with some much needed assistance. Hats off to the people who have put in the hard hours to make these programs and utilities available.
....................................................................
iCreate*, maker of the i5062/i512x controller chips. merged by TM technologies (www.tmtech.com.tw)
The company knows very well what oversized flash drive is. In fact, oversizing 
wouldn't be possible without the help of the controller maker. Oversizing is 
merely an 'undocumented feature' of the controller chip. 

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