Recovering Broken, Unformattable, and Ghost USB Flash Drives

by Nick on September 8th, 2009

EDIT: This information is very out of date at this point. Beware of following this guide on modern systems. As some commenters have mentioned there are better ways of going about recovering Flash drives at this point. Check out Ben’s comment in particular about Chip Genius, the tool is very useful to ascertain what controllers/NAND you are working with.

Welcome again. Today I am going to provide a helpful guide to recover broken USB drives, ghost drives, and drives unable to be formatted. If you are asking questions like “I can’t format my usb drive! Whats wrong?”, you may want to read on.

This guide will also aid in the recover of ghost drives and return the flash drive to it’s actual capacity.

Check to see if your drive exhibits any of these behaviors:

  • Windows says “Unrecognized USB device”
  • You cannot format your USB drive. The format utility also displays a capacity of 8mb no matter the size of your drive.
  • Your drive status light flashes but nothing happens on the OS.
  • Your drive shows up, but when you try to write, it crashes and disappears.
  • Generally, your drive is not functioning correctly.

WARNING: Before you continue with this guide, be aware that, although highly unlikely, using some of the programs in this guide could possibly destroy the physical controller unit on your drive. Only proceed if this is a last resort. I TAKE NO RESPONSIBILITY FOR IRREPARABLE DAMAGE OR LOST DATA.

First of all, a USB flash drive is comprised of two main parts – the Controller and the NAND Flash Chip. This guide is going to explain the use of a program which accesses the controller unit directly to complete formats and recoveries.

NOTE: Since this program accesses the controller unit on your flash chip, I have included 2 programs that do the same thing. Each program has a list of controller access codes. Depending on your controller, one of these access codes may or may not work.

Lets get started!

Step 1

Download the program package and extract it. You will see the programs labeled prog1 and prog2.

Step 2

Remove all your USB Flash Drives. Once you have your drives out, start up ONLY ONE program. Don’t open both! This will cause some serious system related issues.

For prog1, click the lightbulb icon. For prog2, click umptool2090.exe. Once open, both of these programs should look extremely similar.

Step 3

Plug your broken flash drive in. If you do not see the flash drive appear on the program screen or you see “UNKNOWN FLASH”, try the other program.

NOTE: If both fail to recognize your flash, unfortunately you will have to continue your search for an answer.

Step 4

When you have your drive plugged in and it is recognized by our program, click start. No other setup is required. I have preset everything to return your device to it’s original state.

WARNING: If you continuously format your drives, THEY WILL BREAK! Prog2 is notorious for breaking drives. Expect a 15%-20% fail rate. Again, I have set prog2 to minimize this as beast I could, down to ~5%.

If you would like to poke around in the settings panel, there are a lot of interesting features. One that I would suggest is “Information Tab” for prog1, and “Vendor Settings” for prog2. This controls the vendor name information which shows up on the taskbar info bubble, a cool feature to show off to your friends. Other than that, I leave it up to you to figure out the settings AT YOUR OWN RISK. Remember, the more you run the drives through the program, the greater the chance they will break.

NOTE: In program 1, you will be prompted with a password box when you click settings. Leave it blank and hit OK. If it does not allow you access, you can check the .INI file in the root directory for the password if it got changed for some reason.

If you have any questions or would like additional controller codes for prog2, leave a comment and I will respond to you. You may also leave your email addy if you would like me to respond directly to you as well as in the comment thread.


I have gotten my hands on an updated version of the programs which can be found here. All the programs have again been optimized for successfully recovering your USB drives. A few notes though:

  • The “No Loader ISO” error is gone.
  • Changing settings requires a password and the password is blank, just hit okay.
  • Make sure you run the programs as administrator.
  • Do not proceed unless “Flash Type” shows some information. “UNKNOWN_FLASH” means the program won’t work, so don’t try it if it says this.
  • I provide no warranty. By using the programs you agree not to hold me or this blog liable for damages.

Furthermore I will get to all the comments as soon as possible, I know it has been a while, holidays have me busy.

Happy Holidays 🙂

  1. stray permalink

    Hi Nick;

    I have problem with sony 8g. Your programs not recognize my flash. So how I can format? prog2 program was recognize it, but can’t click start and when I click on my flash name, then program is stop working. I don’t know why? :((
    But thanks you. If you have any suggesting, Please tell me. Thanks again.

  2. karinne wallace permalink

    Thanks very much, prog2 worked like a charm right upon opening. Prog1’s light bulb icon for AlcorMP brought up a text box that says “no image file loaded”, and to remove USB devices, re-open Alcor, but doing that doesn’t help- it seems to be missing an essential file. Just a bug report there friend- like I said prog2 worked great and I’m VERY happy that my flashdrive isn’t toastcrumbs.

  3. winmark permalink

    Hi, is there any other way or tweak to forced detect my device?

  4. Hi, I am trying to start the first program (AlcorMP), but I just receive an error message: No reserve image file. And than nothing happens.
    The second one does not recognize my USB Stick.

  5. Manuel permalink

    Hello there, i’ve benn looking for a solution to an “unformatable” 8GB usb key, but every attempt was a failure, today i found your page and voilà, the usb memory started to function again, i have no words!
    I’ll not going to tell you that i’m no newbie, i was about to edit the partition table with a low level editor, even if i suspected that was the partition table inside the memory’s microcontroller; but these programs you gave us!! I think those are used for production and testing, anyway, let’s go to the matter.

    My usb drive works (yeah!), but the program2 (aka Ump_tool, updated version), broke something inside my XP system, i cannot recover my safe remove hardware function (nor icon) in the tray; even more, i went into the properties of any usb memory i connect, and the link that should show the list of the devices i can remove is empty.

    Have you had such an experience before? Can you provide some light for this matter too?


    • Ben permalink

      Beware of AlcorMP! If you run 64 bit Windows, it will install a driver called “mpfilt.sys” that is not compatible. This causes “Failed to start” errors (Code 10) in Device Manager when you re-start Windows and most of your USB ports are disabled! The driver file has to be deleted from the “C:WindowsSysWOW64drivers” folder and then all references to it must be manually removed from the registry. Very time consuming…

  6. Ben permalink

    This is way too hit-and-miss and can potentially disable your USB ports! It is MUCH safer to download “ChipGenius” to identify the Controller Part-Number and Firmware of your USB stick and use that to Google for the vendor-specific tool that will repair the USB stick. Then are numerous online guides on how to do this.

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