USB Flash Drive Not Recognised

[weslstan]

Hey there.

I am travelling at the moment and am at the risk of losing all 1800 of my photographs if I dont sort this out.

My usb stick decided to stop working today, its an 8gb kingston data traveller and whilst the light flashes every 20 seconds its not appearing anywhere.

I presume the fact that the light still flashes is a good thing but thats all it does at the moment.

Any help will be greatly appreciated.

The usb is DataTraveler 101 (DT101)

Thanks,
Wes.

Also ive tried the usb on 4 different computers and it doesnt respond on any of them, so it has to be a problem with flash drive and not the pc's.

 

[raybay]

The Data Traveler is a high failure item... but there are recovery programs that will work. A professional repair-restore can cost $400.
Put it away until you have a budget to have somebody look at it... the more you fool around with experiments and guesses of tech wannabes, the greater the risk that the images are lost forever.

 

[weslstan]

xehqter:

Is there nothing I can try myself? I dont mind paying you to fix it as im sure you are capable but id rather try a few options to fix on this side first.

the thread is called "usb flsash drive not recognised" but I DO NOT get that error when plugging the usb in, I infact get nothing at all except the flashing of the usb light which I assume is a good thing.

Basically Im travelling and every so often I put photos from my camera and move them onto my usb, I went to do this using one of the hostels pc's and they had some kind of virus software installed that began to delete or appear to delete my files, i removed the usb tried another pc and the files where there again.
The pc was slow so I went to an internet cafe and plugged the usb in and thats went it began not responding.

Hope that helps with finding a solution, I know my pictures are still on there and I trust I can get them back.

 

[LookinAround]

[post=720762][Troubleshoot: Windows Won't Recognize USB Hard Drive / Fix Unassigned Drive Letter[/post]

Start from initial troubleshooting Part1. Report back at which step you start getting errors and what you see./do/any system messages/etc.

 

[raybay]

Based on the long history of problems with that particular USB Flash Drive, I will almost guarantee you will need help.
XEHQTER has a lot of useful information on his site, and the experience. You risk losing everything whatever you try... but we doubt you will be able to fix it yourself. It is a hardware problem caused by carrying it in your pocket or bending the USB nose, because it was poorly built. The nose is now damaged and you have no good connection.
If those files and pictures are valuable, you will have to pay for a rescue... and you might have to await a time when you can afford it.

 

[LookinAround]

Ummmm....

From your posts, I read the USB flash drive isnt' working (i.e. Windows isn't acknowleding it exists, e.g. i'm guessing no disk shows up under Disk Managment)

HOWEVER, i don't see anything to assume at this point that the flash drive is damaged beyond software recovery procedures. (It might very well be but you haven't done anything to know that for certain yet)

I'll repeat the advice from my last post.

1. Go to that link in my last post and determine if Windows is recognizing the DEVICE per the instructions under INtial Troubleshooting
2. The important thing to establish is what's occuring in Device Manager when you connect the Device. And try a couple software tools that use something called RAW DEVICE I/O when trying to talk to drive.

There are two software tools that come to mind that use raw I/O to communicate with the device and by doing so can communicate where others often fail
a) Partition Table Doctor (link to the demo version can be found in Part1 of the Troubleshooting guide i provided). The first key question is: Can Partition Table Doctor recognize/indicate it can talk to the flash?

Report back on result/progress and if need be can then also look up the other tool (which will also require more "hand-holding" for you to use it.

/* EDIT */
By the way, look at Part3 of the guide as well to build your own G-parted boot CD. When you build this CD you'll also have a copy of TestDisk to try for recovery (as i see other user actually refers to it as well). It may do the job also (is why you find i talk about it myself in my Guide) and is free so also worth a shot to Partition Doctor seems to have the best success rate (put not perfect) and demo version of PTD at least allows you to see if a) it can talk to the flash and b) can report what the corruption is that it finds

 

[raybay]

Could be, but our shops have handled hundreds of these, and they are bad news... just carrying them in your pocket seems to crack the machine-run cold solder. The data is available when the chip is removed to another device, but rarely have we or other shops around our area been able to recover data directly off of the device. Those sent to companys who perform recovery have been able to rescue the data nearly every time.

 

[LookinAround]

yep. could be (note the accent on the word could)

But when when the only technical data posted is a user saying "its not working" my immediate reaction isn't "Go staight to repairs. No need to bother to run any (even freeware) diagnostic or recovery software before assuming you must spend $$. So just bring it in!"

So even if likely be the case, who wouldn't try check it first themselves for free?

I mean the O.P. (original poster')s own words were (is their words, but my accents to highlight)

Is there nothing I can try myself? I dont mind paying you to fix it as im sure you are capable but id rather try a few options to fix on this side first.

And even if they OP hadn't asked... is only prudent to recommend someone doing something first to at least check it out before simply bringing it in and paying $$

/* EDIT */
And on that note, Westlstan, maybe the quickest and easiest thing to do is simply just
=> Dpwnload the demo (free) version of Partition Table Doctor
=> Determine if it's able to detect/talk to that drive at all
=> Report back yea or nay

 

[weslstan]

Hey Lookinaround.

I download the recommended program and it didnt detect anything.

I have a felling all this is caused by some antivirus programs, I am in another internet cafe now and I plugged another usb drive in and it proceeded to start deleting files it assumed where malicious.

Now with this drive it is 1gb but (300mb of which is used) but is only displaying 3 files but when I click on properties it still says 300mb is being used.

I just dont think it is a hardware problem, is there any other options you can suggest?

Thank you.

 

[LookinAround]

Well, again certainly noting it can very well turn out to be hardware failure but here's some things to try before you decide to throw in the towel (and the USB thumb drive!) at some point along that way

1. Boot into safe mode. (the idea being in Safe mode only the minimal software is started. So if a virus or other program interfering MAYBE it won't start while in safe mode) Try plugging in USB drive after booting into safe mode. If still a problem, try that Partition Table Doctor again while in safe mode
2. In general, See this Guide Troubleshoot: Windows Won't Recognize Your USB Hard Drive
3. Specifically, See Part 3 of the guide. Booting from CD and into Linux would eliminate Windows and all your software that normally loads as the culprit. Can help raise the odds of the problem in fact being your hardware and/or BIOS. Basically this test greatly reduces the chance of the software being loaded from your hard drive to almost certain not the problem (but nothing is 100% certain sometimes with computers!~)
4. Try each of the recovery/management tools you find in the guide Part1. Tho PTD is pretty good a raw physical I/O, there is also another excellent tool that does it tho I didn't list it in the Guide because it can require lots of detail to use the tool to repair a drive. But is easy to use the tool to simply try and detect the drive)

But i need go dig up that other tool. so you can look back at this post and i will update the post with an /*EDIT*/ at the end of the post when i find it (probably not till sometime tomorrow)

/* EDIT! */
(but not the edit about the other tool) but DUH. I should have had you try the instructions below as well. you can go ahead and try step 1 above as it's easy to do BUT certainly before you try burning a CD please do the following (a basic check to reveal some info for me)

• Click Start->Run, enter: msinfo32
• Click the + sign next to Components to expand it
• Click Problem Devices. Anything appear?
• If yes, click on it, then Edit->Select All, Edit->Copy Paste into next post

 

[raybay]

Don't know of a software reason, and there is AMPLE evidence of hardware failures in that particular series of devices.
The real problem is that you never know when you buy them. The device was made by a korean company for use by a once great company, Kingston. Kingston just put their name on this device. They did no make it. But they provided specifications that allowed a yugo instead of an Acura where flash drives are concerned.
The worst company for these problems is SanDisk... same design. Same failures. Just don't carry them in a pocket or purse where they can be subject to slight bending or vibration.

 

[LookinAround]

Just don't carry them in a pocket or purse where they can be subject to slight bending or vibration.

Excellent advice. Wise to be extra careful with these devices

 

[LookinAround]

But is also good to know: Here's just a few things that can cause USB drives to not appear that have nothing to do with hardware failure

1. Problems with a special type of driver found in Windows called "Filter Drivers"

Everyone thinks USB drives don't require special device drivers AND THAT IS TRUE. But filters can be applied to a disk drive IN ADDITION TO (not IN PLACE OF) the Windows built-in device drivers. Thus problems in a filter can result in problems with the USB disk drive device driver which in turn can make it seem the disk and /or driver is not working and sometimes can't even be seen in Explorer or My Computer!
​

2. Unplugging a USB drive without first stopping the USB drive

can result in data corruption and, in turn, cause the drive to improperly load/not appear detetected. This has nothing to with hardware failure but much to do with software issues and data corruption​

3. The drive might be hidden

Actually, forgot about this one. Drives can be hidden in Windows by modifying the Windows registry. This might be done by software applications, (or yourself and not realizing/remembering) OR by viruses! You'll find instructions in Part3 of the Guide on how to check if your device is being hidden​

/* EDIT */
LOL to me. Is time to call it a night. As for 3) it's true the drive can be hidden BUT it's only hidden from view in Explorer and My Computer. I believe Partition Doctor should not have had a problem seeing it. Off to bed. More tomorrow

 

[Tedster]

add this rule: NEVER store ANYTHING on a flash drive you cannot afford to lose. Flash drives by their nature are volatile. Always back the item up elsewhere.

 

[weslstan]

Hey,

So I just downloaded a program called hard disk low level format tool and its displaying the said usb drive....

heres some techy stuff that might help you.

Hard Disk Low Level Format Tool 2.36 build 1181; http://hddguru.com
SMART Attributes for ST380011A 8.01 [80.02 Gbytes]

Attribute Current Worst Raw Note
----------------------------------------------------------------------------------
Att: 1 Read error rate 59 51 204721611
Att: 3 Spin up time 98 98 0
Att: 4 Number of spin-up times 100 100 210
Att: 5 Reallocated sectors count 100 100 0
Att: 7 Seek error rate 87 60 498908800
Att: 9 Power-on time 75 75 22736
Att: 10 Spin-up retries 100 100 0
Att: 12 Start/stop count 97 97 3343
Att: 194 HDA Temperature 38 53 38 (38 degrees)
Att: 195 Hardware ECC recovered 59 51 204721611
Att: 197 Current pending sectors 100 100 0
Att: 198 Offline scan UNC sectors 100 100 0
Att: 199 Ultra ATA CRC Errors 200 200 0
Att: 200 Write error rate 100 253 0
Att: 202 Unknown 100 253 0

urrent date and time: 2009-2-15 21:26:02
Hard Disk Low Level Format Tool 2.36 build 1181; http://hddguru.com
Device details for ST380011A 8.01 [80.02 Gbytes]

Model: ST380011A
Firmware Revision: 8.01
Serial Number: 4JV57R9X
Buffer size: 2097.15 Kbytes

PHYSICAL PARAMETERS:
LBA mode is supported
LBA-48 mode is not supported
Sectors available with LBA commands: 156,301,488
Sectors available with LBA48 commands: 0
Full device capacity: 80,026,361,856 bytes

SECURITY:
Security features is supported
The device is currently not locked

FEATURES:
SMART is supported
HPA (Host-protected area) is supported
AAM (Automatic acoustic management) is not supported
Streaming feature set is not supported

QUEUING:
Command Queuing is not supported by the device

 

[LookinAround]

Thank fact that's in fact providing info (i.e. detecting it) is at least some news@!

Please run the msinfo32 instructions in prior post and then post results too. Thanks~

/* EDIT */
And does that mean you've already reformatted the drive and gave up on your old data??? or is this some output you can get but NOT actually format the drive?

 

[LookinAround]

As to Tedster's post

add this rule: NEVER store ANYTHING on a flash drive you cannot afford to lose. Flash drives by their nature are volatile. Always back the item up elsewhere.

I couldn't agree more with Tedster's advice. By definition, all flash memory devices have a limited lifetime before they begin to fail. This is true if only due to the number of read/write cycles applied to flash memory (and totally aside from any physical damage that might be sustained from carrying it around). So anyone reading: always back up your flash drives!​

As to the data you (Westlan) provided
I just looked a bit closer at the report header. And I'm not sure the data you report is actually about the thumb drive.

Hard Disk Low Level Format Tool 2.36 build 1181; http://hddguru.com
SMART Attributes for ST380011A 8.01 [80.02 Gbytes]

When i google ST380011A i'm getting hits which tend to indicate it's a Seagate Barracuda internal 80GB hard drive! Could you have gotten a report on the wrong device? Did it report any other devices? It might not be finding the device either?​

As to what next

First a brief explanation
=> For each new USB device connection, Windows creates a USB device descriptor and saves info about the connected device
=> This data is not deleted when the device is disconnected. It's deleted when the device is uninstalled!
=> Will spare the detail but Windows saving this data can be a mixed blessing. Usually helps, sometimes it causes errors

Download: drivecleanup. Disconnect the thumb drive. From a command prompt window (Start->Run, enter: cmd) type

[B]drivecleanup -T [/B]   [I]to only display ([U]but not yet actually delete[/U]) disconnected USB drive device data[/I]
[B]drivecleanup [/B][I]  to actually perform the deletes[/I]

a) then Disconnect all devices (USB and otherwise).
b) Reboot
c) Plug the thumb drive in and can try both PTD and the HDD formatting tool again to see if they find anything new. The odds are long but not impossible!​

 

[tipstir]

Wow long post.. I would recommend before you use such a device in the future is to format it to FAT32. A lot of these JumpUSB and SD/MicroSD etc are in FAT16. So much issues with these. I never had problems with Kingston except for the wrong format the drive was being used. Once you fix that it's okay. If the unit is acting up take it out place it into a ziplock bang with a paper towel for moisture. Stick it into the freezer for 2 hrs than take it out let it get back up to room temp but leave it in the bag with the paper towel.

 

[xehqter]

This post is so full of miss-information I don’t know where to begin.

1. There are no software tools for recovering data from physically damaged flash drives. It sounds like when you unplugged the flash drive it damaged the lookup tables(see: how flash drives fail) Lets hypothetically say, you had direct logical access to the NAND memory which you’ll never get from the flash drive. Data isn’t stored sequentially, meaning 0,1,2,3,4. Data is stored by least used block in a bank, meaning it can be arranged as 3,0,2,8,1, on top of that to improve speed data is stripped across blocks, NAND chips, or bytes. Every time I get a flash drive in it’s a puzzle, meaning I have to de-obfuscate whatever the controller is doing before I can read the data. It’s very challenging. There are many programs that can recover deleted data but I repeat, there are no programs that let you recover data from failed USB flash drives.

2. Westlan said he tried it in two computers, it didn’t work in either. He unplugged it while it was deleting files and when he reattached the drive it no longer worked. That’s classic damage to the lookup table caused by the erase cycle.

3. If you DON’T care about the data, you can use the mass production tool for that drives controller (open up the drive & look for the small square chip). This is equivalent to a low level format, it tells the controller to re-initialize the drive as-if it came from the manufacture, it wipes the NAND memory chip and re-creates the lookup tables. You can download those tools from flashboot.ru. This is an Advanced tool, you need to know device specific information about the drive, (SLC, MLC, Capacity, etc) however you can do some neat stuff, like make the drive think its 100GB, change the manufacture info to say what ever you want, enable/disable USB 1.1/2.0 support, etc. Most likely you'll cause more harm than good using these utilities.

4. Filter Drivers, Bad USB Controllers, and network drives with the same drive letter CAN cause windows to not recognize the drive. In those cases, plug the drive into another computer, if it works, that is likely the cause. In this case he tried that and it didn’t work.

5. Unplugging a USB flash drive while its writing CAN cause damage to the internal lookup tables on the flash drive. (read how flash drives fail) Before a write can be completed the block must be erased, if you unplug the drive after the erase occurs but before the new block is written it will cause exactly this problem.

6. SanDisk sucks, they constantly reinvent the wheel w/ their designs and many of their controllers encrypt data on the NAND chip making it impossible to recover (unless you know the key). This isn’t U3 or password protecting the flash drive, the controller adds a layer of encryption on its own.

7. Why are you downloading a program called “Low Level Format” if you care about the data? The device listed is a 80G Seagate HD, not your flash drive. Flash drives don’t support SMART.

8. Drives are formatted as FAT32 or FAT16 for a reason, because that’s what the controller’s firmware is optimized for. Optimized meaning, wear leveling, individual blocks are only good for a specific number of writes, depending on the controller/firmware formatting with a different file system “may” increase the chances of drive failure. Often a special bank (FAT bank) is reserved specifically for that FAT because its constantly written to. If you change the file system the tables will be outside this FAT bank.

9. Weak solder joints can cause the flash drive not to work, if you open up the drive and apply light pressure to the controller and NAND memory chip (see: how flash drives fail). I’ve recovered data from hundreds of flash drives, I only had two instances where this was the case. Most damage is caused by power surges, aging NAND chips, erased lookup tables, and damaged usb connectors.

10. Stick it in the freezer for two hours??? WHAT!!

People have a perception that flash drives don’t fail, often people replace the drive before the drive has time to fail. They are durable; I’ve recovered data from drives that were run over, put through the wash and dryer, in a fire, etc. They are very robust but the underlying technology has its flaws.

My Advice, Backup on different media, be it remote, hard drive, or flash drive. Only saving your data on a flash drive doesn’t constitute an offsite backup

 

[kimsland]

7. Why are you downloading a program called “Low Level Format” if you care about the data? The device listed is a 80G Seagate HD, not your flash drive. Flash drives don’t support SMART.
...
10. Stick it in the freezer for two hours??? WHAT!!

Hmm point 7 was interesting.
And point 10 was funny. But it is true, if your Harddrive fails, sometimes (sometimes ) if you put the drive in the freezer (wrapped in plastic bag) you can access a drive that couldn't read before. But usually only for about 15mins, just enough time to backup something really important.

Anyway, I have proved that sometimes this works

Edit:
Just to add to your Edit

Only saving your data on a flash drive doesn’t constitute an offsite backup

Yes a flash drive is an external backup source for many (I'd go as far to say- Most users)

 

[xehqter]

Hmm point 7 was interesting.
And point 10 was funny. But it is true, if your Harddrive fails, sometimes (sometimes ) if you put the drive in the freezer (wrapped in plastic bag) you can access a drive that couldn't read before. But usually only for about 15mins, just enough time to backup something really important.

Anyway, I have proved that sometimes this works

Edit:
Just to add to your Edit

Yes a flash drive is an external backup source for many (I'd go as far to say- Most users)

I've heard of people doing that with Hard Drives, I don't see how that would make any difference with a flash drive. <sarcasm> How about this for crazy urban legends, I saw a youtube video of some guy reworking PCB using a toaster oven. We could start a urban ledge that taking the plastic off and sticking the drive in a toaster oven set @ 350F will rework the solder joints and fix the drive.. its plausible</sarcasm>

I meant many people store the only copy of a file on their flash drive and consider that an off site backup because its not stored on a hard drive locally.

 

[LookinAround]

I'm going to add in my comments in italicized blue lettering interlaced with your quote
But before I address the topics below, i'll first honestly say "thanks xehqter" for providing one of the livelier discussions/debates in a thread i've seen in quite a while (and i'm saying it matter-of-fact, not being facetious)

This post is so full of miss-information I don’t know where to begin.
1. There are no software tools for recovering data from physically damaged flash drives. It sounds like when you unplugged the flash drive it damaged the lookup tables(see: how flash drives fail) <snip>

We agree that if raw physical I/O is impossible (e.g. due to hardware damage) then, yes, of course, there can be no software based recovery if only for the simple fact there is no software access to the data. Beyond that your argument begins to get a bit fuzzy. So if you could elaborate...

As i read your post, you place remaining problems under "Lookup Table Corruption" (for convenience i'll simply use LT for Lookup Table). You've labeled any LT Corruption as "Can't be solved by software recovery". And if so, i need a better explanation of what you're saying:

• I admit I'm not intimate with the differences (if any) between what you refer to as LT Corruption vs "Partition Table Corruption" (i'll be refering to PT Corruption for short) We know, in fact, there are several software tools that provide for recovering from PT Corruption
• This tells me there are certainly some forms of PT corruption that are software recoverable. Yes? But i hear you say ZERO % LT corruption is software recoverable. So could you elaborate on the distinction between the two where some of PT Corruption has a significantly greater then 0% chance for software recovery but LTC for your case simply states "Corruption = 0% chance". Period.
• And if i recall correctly, doesn't your site offer some software tools to try in case of corruption? (TestDisk comes to mind) Please correlate those positions on software recovery i read on your web site to the ones you now state here
• Could you also explain products like Disk Internals Flash Recovery Software? I've never used it so can't say it works but am i hearing you state it's smoke and mirrors and you could righteously sue them for consumer fraud? (And I'm frankly being serious here as well as seems to me it comes back to YOUR position of the problem = 0% chance of software recovery success

​

2. Westlan said he tried it in two computers, it didn’t work in either. He unplugged it while it was deleting files and when he reattached the drive it no longer worked. That’s classic damage to the lookup table caused by the erase cycle.

OK. Agree. Sound like classic damage to LT. And since the same "classic damage to PT can be recoverable by software... we're back to we know at least reasonable chance for PTC but still your flat statement of Zero % for LTC... back to needing to have that explained.​

3. If you DON’T care about the data, you can use the mass production tool for that drives controller (open up the drive & look for the small square chip). This is equivalent to a low level format, it tells the controller to re-initialize the drive as-if it came from the manufacture, it wipes the NAND memory chip and re-creates the lookup tables. You can download those tools from flashboot.ru. This is an Advanced tool, you need to know device specific information about the drive, (SLC, MLC, Capacity, etc) however you can do some neat stuff, like make the drive think its 100GB, change the manufacture info to say what ever you want, enable/disable USB 1.1/2.0 support, etc. Most likely you'll cause more harm than good using these utilities.

4. Filter Drivers, Bad USB Controllers, and network drives with the same drive letter CAN cause windows to not recognize the drive. In those cases, plug the drive into another computer, if it works, that is likely the cause. In this case he tried that and it didn’t work.

I know where you're going here and "kind of agree" with the statement but if and only if one were to be careful to test on two VERY different computers. But assuming they're both Westlan's computers and the problem is the result of (for example) a bad Iomega filter driver. The filter gets created when the Iomega is connected the first time. The filter is NOT removed if the Iomega is disconnected. It's only removed when the Iomega is uninstalled) .... Thus, it's very probable that Westlan would use the same Iomega (which creates the same bad filter) and uses the same Sandisk flash drive on BOTH computers. And, voila! The flash doesn't work on either. So again, a case where the simple observation of "not working" is not sufficient to give the flash drive the "kiss of death" and immediately ship it for repair

<< Well, and that's all for now as is quite late, but happy to continue with more if still need to >>​

5. Unplugging a USB flash drive while its writing CAN cause damage to the internal lookup tables on the flash drive. (read how flash drives fail) Before a write can be completed the block must be erased, if you unplug the drive after the erase occurs but before the new block is written it will cause exactly this problem.

6. SanDisk sucks, they constantly reinvent the wheel w/ their designs and many of their controllers encrypt data on the NAND chip making it impossible to recover (unless you know the key). This isn’t U3 or password protecting the flash drive, the controller adds a layer of encryption on its own.

7. Why are you downloading a program called “Low Level Format” if you care about the data? The device listed is a 80G Seagate HD, not your flash drive. Flash drives don’t support SMART.

8. Drives are formatted as FAT32 or FAT16 for a reason, because that’s what the controller’s firmware is optimized for. Optimized meaning, wear leveling, individual blocks are only good for a specific number of writes, depending on the controller/firmware formatting with a different file system “may” increase the chances of drive failure. Often a special bank (FAT bank) is reserved specifically for that FAT because its constantly written to. If you change the file system the tables will be outside this FAT bank.

9. Weak solder joints can cause the flash drive not to work, if you open up the drive and apply light pressure to the controller and NAND memory chip (see: how flash drives fail). I’ve recovered data from hundreds of flash drives, I only had two instances where this was the case. Most damage is caused by power surges, aging NAND chips, erased lookup tables, and damaged usb connectors.

10. Stick it in the freezer for two hours??? WHAT!!

People have a perception that flash drives don’t fail, often people replace the drive before the drive has time to fail. They are durable; I’ve recovered data from drives that were run over, put through the wash and dryer, in a fire, etc. They are very robust but the underlying technology has its flaws.

My Advice, Backup on different media, be it remote, hard drive, or flash drive. Only saving your data on a flash drive doesn’t constitute an offsite backup

 

[xehqter]

We’re talking about two different things, you’re talking about filesystem damage and I’m talking about lookup table damage. Filesystem damage occurs on the top layer (what the OS sees). Programs like TestDisk, PhotoRec, chkdsk, or Disk Internals Flash Recovery work on this level. Lookup table damage occurs on the bottom layer (Controller/NAND). The controller remaps sectors on every write to prolong the life of the NAND chip, it keeps these mappings in a lookup table. Ie: LBA Sector 0 is @ Block 324, LBA Sector 1 is @ Block 233, … each time a sector is written to the LBA sector is mapped to a different block on the NAND chip.
As the flash controller doesn’t give you RAW access to the physical NAND chip there are no applications which can repair this type of damage, the NAND chip must be removed, dumped, and the data reconstructed.

When you’re talking about RAW physical I/O you mean the virtual LBA environment that the flash drive’s controller creates. When I’m talking about RAW physical I/O I’m talking about the RAW data on the NAND chip. Virtual Sector 0 (which stores the partition table) is not stored in Block 0 of the NAND chip, the controller uses lookup tables to translate between Virtual Sector 0 and the physical block in the NAND chip. Lookup tables are not accessible via the virtual layer.

I highly doubt it has anything to-do with a filter driver.
1. He tried it on four different computers @ different locations w/ different owners.
2. He said he unplugged the drive while it was being written to.
3. The flash drive was working just fine until he unplugged it while data was being written to it.
4. He said the light flashes for 20 seconds, then dies, again another sign that it’s not a computer issue.

In hard drive terms that equates to the drive making clicking noises or not spinning. Sure there is that 1 in 1000 chance it’s a bad power supply or cable but more likely than not it’s a bad drive. Where are you reading Iomega or SanDisk from? Neither were mentioned by him.

 

[LookinAround]

Taken me several days to respond due to both being busy as well as trying to look a bit deeper into our topic...

We’re talking about two different things, you’re talking about filesystem damage and I’m talking about lookup table damage

From the start, I’ve been talking about differentiating problems as being either due to hardware damage vs. data corruption so, in fact, I think we’re not far off from one another. As regards to all your references to "lookup table damage" i'll start by saying, in general,

• The concept and use of look-up tables (LUTs) are fairly common in computing systems. One can find them used to help implement a variety of data and memory management functions
• I’ll add that I understand look-up table usage whether for flash memory wear-leveling or its other forms for use in other common computing functions
• I mention all this so, in part, you understand that when I first read your repeated references to "look-up table damage" I read that as inferring a data corruption issue (vs. hardware/controller damage issue) Continuing with this line-of-thought for the moment
  • What you're calling "lookup-table damage/corruption" would prevent software from accessing some parts (but not all parts) of a flash drive's physical data in its logical order (as the logical to physical order is what's, in fact, stored in the LUT)
  • But i don't see why "lookup-table damage/corruption" should prevent a controller from providing software with a dump of ALL physical data (simply ignoring the lookup-table and not even trying to map physical to logical). This is assuming a command to dump physical vs. logical data exists (and i would hope so if only to circumvent lookup table corruption!)
  • In fact, what i hear you describe as your data recovery process is essentially what i'm describing! And could be done via software if a physical data dump could be done (simply ignoring the lookup table). You are dumping all the physical data and then algorithmically attempting to reassemble what you can back into logical order?
  • Am just asking (not trying to challenge you) but do you know for a fact that flash memory device command set doesn't support a physical data dump? i.e. simply dumping physical data regardless of look-up table content. Sure makes sense should be one if only for the above reasons!

As for your additional comments i'll insert my comments in blue below

I highly doubt it has anything to-do with a filter driver.
1. He tried it on four different computers @ different locations w/ different owners.

You're right about the four different computers (i hadn't re-read the post when i mentioned the case of just two). And while you're right about 4 different computers greatly reducing the probability i think OP simply said 4 different computers.. is a bit of an embellishment to extend that to 4 different computers @ 4 different locations and 4 different owners​

2. He said he unplugged the drive while it was being written to.
3. The flash drive was working just fine until he unplugged it while data was being written to it.

Interesting note about corruption due to this problem... this type of error is so frequent with usb flash devices i know the industry has tried addressing this problem with the physical data (and only guessing or hoping they would've done something similar with LUT or why bother just fixing the physical data to then lose it all via LUT problem?) Specifically, your descripiton of the problem assumes the SAME block is first erased and THEN over-written. This is not true. A different (not the original) block is first erased and then written and the block pointers updated. The original data can then be safely erased later thereby trying to avoid this situation (albeit not 100% successful at it)​

4. He said the light flashes for 20 seconds, then dies, again another sign that it’s not a computer issue

WHAT? I believe they said the light is flashing but nothing else appears. Perhaps i overlooked it or could you indicate the Post # where OP said it flashes and then dies????​

Where are you reading Iomega or SanDisk from? Neither were mentioned by him.

It wasn't clear in my post but i simply chose those 2 company names to explain my point about filter drivers (I thought it read better then saying Company A and Company B). My post had simply stated "and the problem is the result of (for example) a bad Iomega filter driver....." which didn't make it clear the companies just served as examples ​

Finally, will add, on the topic of whether software can help recover when LUT damage/corruption.. i hope to be able to post back again soon in the future on that and whether or not a physical dump can be provided via the controller regardless of LUT

 

[xehqter]

If you want to find a way to access the raw data in NAND memory feel free. I won’t say it’s impossible however I will say there are hundreds of different controllers from many manufactures and there is no “public” universal interface to do this.

I don’t believe your diagnosis of his problem is correct, and I have the feeling you think mine is just as wrong so I’ll leave it at that. If he can’t get his data with your methods he can contact me or any other data recovery shop that specializes in NAND memory.