Recovering a Partially Formatted USB Thumb Drive

To attempt to recover a USB drive back to usable state, you should try these commands.

First it should be noted that you should have Windows 7 installed on a computer that you have access to, so that you can use the diskpart command. You'll also need to have administrator access on this computer.

1. Click on the Start Orb.
2. Type cmd into the search box.
3. Shift + Right Click on the CMD icon.
4. Click on Run as Administrator.

From here, we are going to type in diskpart and run the following commands.

C:\Windows\system32>diskpart

Microsoft DiskPart version 6.1.7601
Copyright (C) 1999-2008 Microsoft Corporation.
On computer: DYGEAR-PC

DISKPART>

From here we are going to type list disk to find the current drives connected to the computer.

DISKPART> list disk

  Disk ###  Status         Size     Free     Dyn  Gpt
  --------  -------------  -------  -------  ---  ---
  Disk 0    Online           14 GB      0 B
  Disk 1    Online           74 GB      0 B
  Disk 2    Online          698 GB      0 B   *
  Disk 3    Online           15 GB      0 B

The 15GB drive is the drive we are looking for, as that's the size of our USB Thumb Drive. So to select that drive, we run the command select disk 3.

DISKPART> select disk 3

Disk 3 is now the selected disk.

If you are not sure if this is your drive, you can request details about the drive by running the command detail disk after you have selected the disk.

DISKPART> detail disk

Corsair Voyager Mini USB Device
Disk ID: 00000000
Type   : USB
Status : Online
Path   : 0
Target : 0
LUN ID : 0
Location Path : UNAVAILABLE
Current Read-only State : No
Read-only  : No
Boot Disk  : No
Pagefile Disk  : No
Hibernation File Disk  : No
Crashdump Disk  : No
Clustered Disk  : No

  Volume ###  Ltr  Label        Fs     Type        Size     Status     Info
  ----------  ---  -----------  -----  ----------  -------  ---------  --------
  Volume 4                             Removable     15 GB  Healthy

After we have correct drive, we can select any partitions on the drive select by doing select volume and then the volume number like in our case select volume 4.

DISKPART> select volume 4

Volume 4 is the selected volume.

From here, we will try to recover the drive to a useable state. We are going to attempt to reformat the drive first. FORMAT RECOMMENDED OVERRIDE is the safest way to format your drive back to a normal state.

DISKPART> FORMAT RECOMMENDED OVERRIDE

DiskPart has encountered an error: The system cannot find the file specified.
See the System Event Log for more information.

Should that not work, such as shown above, we can try to run a format command that tells it how to format the drive in our case we use FORMAT FS=NTFS LABEL="Windows7" QUICK COMPRESS.

DISKPART> FORMAT FS=NTFS LABEL="Windows7" QUICK COMPRESS

DiskPart has encountered an error: The system cannot find the file specified.
See the System Event Log for more information.

In our case, this still does not work. So we attempt to clean the whole drive with the command CLEAN ALL.

DISKPART> clean all

DiskPart has encountered an error: Incorrect function.
See the System Event Log for more information.

If we still are having trouble with the drive at this point. Let's try and list the partitions again, see if any changes have been made to the drive with LIST PARTITION.

DISKPART> list partition

There are no partitions on this disk to show.

As there as been a change, let's see if we can get the drive online with ONLINE DISK.

DISKPART> online disk

Virtual Disk Service error:
This disk is already online.

As the driver is online we can now try and clear any attributes that might be in our way such as the read only attribute. We run ATTRIBUTES DISK CLEAR READONLY.

DISKPART> attributes disk clear readonly

Disk attributes cleared successfully.

Let's see if we can put a boot record on there with CONVERT MBR.

DISKPART> convert mbr

DiskPart successfully converted the selected disk to MBR format.

DISKPART> create partition primary

DiskPart succeeded in creating the specified partition.

DISKPART> select part 1

Partition 1 is now the selected partition.

DISKPART> active

DiskPart marked the current partition as active.

DISKPART> format fs=NTFS label=USB quick

DiskPart has encountered an error: The system cannot find the file specified.
See the System Event Log for more information.

DISKPART> format quick

DiskPart has encountered an error: The system cannot find the file specified.
See the System Event Log for more information.

DISKPART> assign letter F

DiskPart has encountered an error: The system cannot find the file specified.
See the System Event Log for more information.

DISKPART> list volume

  Volume ###  Ltr  Label        Fs     Type        Size     Status     Info
  ----------  ---  -----------  -----  ----------  -------  ---------  --------
  Volume 0     V   Video        NTFS   Simple       698 GB  Healthy
  Volume 1     D   SSD          NTFS   Partition     14 GB  Healthy
  Volume 2         System Rese  NTFS   Partition    100 MB  Healthy    System
  Volume 3     C                NTFS   Partition     74 GB  Healthy    Boot
* Volume 4                             Removable     15 GB  Healthy

As noted all of these commands failed from that point. So we should try one last thing to get the drive working again. In this case, what you should do is uninstall the drivers for the USB thumb drive and then reinstall the drivers again after restarting your computer.

---

Take a look at the Format utility from the SD-CARD Organization.

Or you could try using a Windows 98 Boot Disk after using Lexar's USB Flip the Removable Media Bit Tool.

Use the HP Drive Key Boot Utility or HP USB Disk Storage Format Tool 2.2.3, command line or GUI version.

Mark Tomlin's post didn't help me, fdisk from linux did.

fdisk /dev/sdX

This will give you the fdisk prompt:

Command (m for help):

It's intuitive and you can use the following options:

c (to activate DOS-mode, although it may not be necessary)
n (to create a new partition, fdisk will suggest sane values like partititon number and size - for a thumb-drive you'll most like want a full-disk partition, so you'll mostly press <enter> here)
t (choose c for a FAT 32 (LBA) partition type)
a (optional, to flag the pen-drive as bootable)
w (to write changes to disk and exit)

And you're done. Obviously, this procedure will destroy all data in your thumb drive, but the original question pertains to recovering a "dead" drive into a usable state, not to recover its contents. (i'd comment on James T's answer but apparently i need more points for than than to write an answer)