Solved! How to fix a write protected USB thumb drive

Today I got a USB 4GB flash disk from a colleague requesting for my help to delete some files in it.

Unfortunately, the files couldn’t be deleted because the thumb drive is write protected.

With permission from my colleague, I was allowed to format the thumb drive just to recover the disk space and to make it usable again. However, the format process failed with the error stating that the disk is write-protected.

And so I began trying to remove the write protection problem by trying the following methods:

  • Edited the registry
  • Using diskpart to remove the read-only
  • Formatting using Windows or Linux machine
  • Removed read-only permissions from drive properties
  • Third-party tools like HP USB Disk format tool
  • Setting advanced sharing to have permissions with full control

Basically all the above methods failed to work and took a total of 4 hours to troubleshoot.

In the end, this write-protected USB solution worked for me and I hope it will solve your problem too.

But be warned, this method will * delete and format the content of your USB *, so ensure to copy your files to somewhere safe before trying this. This is assuming you can even see and access your files.

  1. Step 1: Find your USB’s VID and PID using Chip Genius v4. Once downloaded, unzip and run ChipGenius_v4_19_0319.exe


  • Step 2: Go to Flashboot to search for your USB’s VID and PID.

Based on the result, you can verify what’s your usb’s memory chip. For the screenshot above, it’s the following SC908SN/AU6989SN [E512] -F/W D82B.

See if there are any available utils. If not, proceed to the next step.

  • Step 3: With the Chip details, Google [Chip Number] + Tool, so for e.g. AU6989 Tool


Click on the link which contains your chip details with Flash Drive Repair.

  • Step 4: On the page, there will be instructions on how to install and fix your USB. Be warned that there are way too many ads on this page which might confuse you on which link to click on.The correct download link looks like this.


  • Step 5: Once downloaded, you can proceed to launch the tool which should detect your thumb drive.

Assuming you have downloaded the correct tool to flash your corrupted usb disk, this method should fix and render your disk usable again.

Alcor Flash Drive Repair Write Protected

Once my disk was detected, I clicked on Start for the tool to begin fixing and formatting my thumb drive.

When completed, my USB disk works normally again.

I hope this helps anyone encountering the same problem.


About the author

Hello there! My name is Bob Lee, and I have honed my skills as a web developer and technical wordsmith, focusing on the creation and evaluation of web applications.

For more than ten years, I’ve navigated through various roles such as an entrepreneur, blogger, developer, and tech enthusiast, thoroughly enjoying each experience.

To keep track of time and meet deadlines, I rely on, an essential tool that significantly enhances my daily productivity.


  • Hi Bob,
    I would like to thank you for your advice and now i can use my Sandisk ULtra 32gb.
    Your solution is the best and working fine for my case.


  • Thanks for leaving a feedback and I’m happy to know that this solution works for you.

  • THANKS first of all.i really want to thank u to show a good my 32gb pendrive works greatly.thanks a lot .u saved my 32gb pendrive.

  • Thanks Bob for this solution. Right now I am using my office laptop with no admin rights thus I will not able to install any new software. So cleaning my pendrive is still an open task for me :(. However before I try it as soon as i get a machine with full access, I wanted to check with you in case if you are aware why and how this problem “Disk is write-protected” happened in first place ??!

    Been on the same road as you, tried regedit and cmd methods, but you hit gold! thank you for posting

  • thhhhanks a lot with all world languages
    this is first time in my life leave a comment
    you are the life & time saver

  • I had lost all hopes as i tried all methods and had given up and was about to throw the pen drive and thought will try this last option – USB’s VID and PID.
    It worked. Thanks a lot.

  • Hi Bob
    my USB Device is (sanDisk) with VID = 0781 PID = 5567
    how can i know my usb’s memory chip, it do not appear in chipGenius

    plz help me.

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