I ordered a bunch of 1GB usb drives from a semi-shady Chinese company. Most of them work just fine, but a couple of them won't let me format them because they are "write-protected." There is no write protection switch on the device. I have exhaustively tried the following:

  • Windows format: "The disk is write protected"
  • HP USB Disk Storage Format Tool: "Device media is write-protected"
  • Changing registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\StorageDevicePolicies to 0
  • diskpart clear attributes readonly
  • diskpart clean: "Diskpart has encountered an error: The request could not be performed because of an I/O device error. See the System Event Log for more information." (The System Event Log only contains the error: The IO operation at logical block address 0 for Disk 1 was retried.)
  • HDD Low Level Format Tool: "Format Error occurred at offset 985,595,904: 1117 - Device I/O error" and hundreds of similar errors
  • Sacrificing a lamb to the USB gods
  • Starting in safe mode with command prompt and running format, diskpart, and chkdsk

So do all these I/O device errors mean that these USB drives are just totally screwed? Is there any way to get more information about the problem?

  • Throw them away, they are crap. You can get 1GB USB stick at Amazon USA already for around or below US$ 2. (Naming that tool "HDD Low Level Formatting Tool" made me chuckle a bit, the developers of that tool surely have a sense of humor ;)
    – user274116
    Dec 17 '13 at 6:46
  • The joke being that there's really no such thing as a low level format anymore? Anyway, I would just buy more but they have a custom logo.
    – Agargara
    Dec 17 '13 at 6:50
  • Yes, especially there is no such thing as LLF for flash-based storage :) It's sad to hear that the logo/branding prevents you from using an alternative. The sticks are not to save, unfortunately.
    – user274116
    Dec 17 '13 at 6:57
  • One more important thing: Do not use those defective sticks anymore! You might be tempted to partition the stick to use the intact area (not sure whether that would make much sense on a 1GB stick anyway), but the wear-leveling of the flash controller will, over time and depending on write cycles, try to utilize all flash memory cells to spread wear evenly over the whole flash. You will have no control over which Flash cells are written, no matter how you might partition the stick... (If the stick would be the cheapest of the fakes without any wear leveling, then this would be even worse...)
    – user274116
    Dec 17 '13 at 7:16
  • Go with a better branding company. I'm partial to 4imprint. I took the liberty of selecting a few filters for the product you described It's a more expensive product, but it will work for years to come.
    – PsychoData
    Jan 28 '14 at 0:37

My answer to this question is similar to the answer I had given for this question Flipping the Removable Media bit -- alternatives to BootIt?

To summarize

You can try using Mass Production tools to reprogram the microcontroller in your USB Flash Drive. However this procedure varies for all USB Flash Drives. Most Mass Production tools are used to repair USB Flash Drives or to add or remove CDFS Partition; Some of these MP Tools can also be used to add/remove write protection.

The general procedure to reprogram your USB Flash Drive to add/remove write protection is as follows:

Download and Run Chipgenius and find out the VID and PID of your USB Drive. http://agnipulse.com/2010/03/chipgenius-and-usbdeview-usb-information-tools/

Go to http://flashboot.ru/iflash.html and enter the VID and PID of your USB Drive.Check if there are any MassProduction tools available and download them. Then you will have to figure how to use it.

Check this for detailed guide on how to do this.(In this guide the MPtool is being used to repair a fake USB Drive) http://agnipulse.com/2010/04/how-i-fixed-a-fake-64gb-usb-drive/

Warning - The procedure varies for different USB Flash Drives and you may end up with irreparable USB Flash Drive.


I have successfully used MPTools on Transcend Jetflash USB Drives for various purposes such as flipping the removable bit or adding a cdfs partition. The MPtool for JetFlash USB Drives is called AlcorMptool and this MpTool has the option to flip the removable bit. Another reason why I feel comfortable to use JetFlash USB Drives is because it can be fixed easily if something goes wrong.


  • worked for my kingston 4gb Datatraveller used SK6211_6281_Kingmax_U-Drive_PD-07 utility. The process got stuck in the middle so had to kill it but the pendrive started working after that. thanks a lot ! Jan 29 '14 at 20:03

If the problem is persistent with the drive and you still can't copy files to it or format it after:-

  1. You tried removing read-only permission from the drive properties
  2. You tried formatting from Windows
  3. You tried formatting from CMD using DISKPART
  4. You tried editing the Registry solution (for WriteProtect word)
  5. You tried the different free online tools like HDD LL Format tool and HP Format Tool

Then your drive is corrupt and needs the internal chipset S/W to be flashed, i.e. repairing the USB software. The steps below will lead you to get a small program to run on your USB memory-stick which is specific to your MANUFACTURER (make) and PRODUCT (model). If you don't want to go through the headache of the manufacturer's technical support then do it yourself as follows:-

  1. Get Chip Genius portable application which you will use to find the VID and PID of the USB stick chip.
  2. Search for the tool to repair your USB stick S/W from FlashBoot website. Search using your VID and PID from the previous step.
  3. Search on Google for the name of the application you find in the "UTILS" column in the page from step 2 and the first link on Google Results (usually) will take you back to the FlashBoot website to download the utility to get your USB drive repaired.

It worked for me for my Kingston Data Traveler flash drive. It didn't work with all the common options for fixing the USB drive having "write protected", but the above solution I found after hours and hours of searching online and asking my computer-geeks colleagues.

Hope this helps!


To further expand bbalegere's answer, what I did that completely fixed my exact problem as yours was I used ChipGenuis to figure out what the controller vendor is. ChipGenuis will also tell you the contoller part number which you can use to find the correct flash tool for your exact model of flash drive since there are a lot of tools for a specific vendor.

After figuring that out, I went to this Russian website that listed all sorts of flash tools here:


Make sure you're using Chrome so they can translate the website for you.

Click on FILES, then on the right side, find the correct vendor. Mine was Phison. Click on the vendor, and that should bring up all the flash tools available for the vendor. Luckily for me, they had a flash utility tool that was able to reformat the flash drive for me. I also tried every option you did, except for the sacrificial offering - I did not have a goat handy and my dogs are just too damn cute. After spending hours, this is the only thing that would work for me.

Good luck!!


I don't know of anything you can do to fix those errors.

It's highly likely that all your drives are in fact "fake" - they either report a larger capacity than they actually have, they use substandard factory-rejected flash chips, or both. This is extremely common: in fact, it's virtually guaranteed that any unbranded flash memory bought from China is going to be bad. (I've even got bad name-brand SD cards from "trusted" Amazon sellers.) The only way to guarantee that you're getting a good product is to buy from a reputable reseller (Newegg, Amazon (and not a third-party "marketplace" merchant), etc.). Even then, it's a good idea to run h2testw on it before you use it to store files.

I recommend that you try this on all your "good" drives and see what it tells you.

  • I tested a few of my good drives and they showed no errors. My guess is they throw in a few fake garbage chips with the good ones, with the hope that you won't have time to test ALL of them.
    – Agargara
    Dec 19 '13 at 0:39

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