I formatted my 16GB pen drive with the NTFS file system in windows vista. After that I started copying some files. However, only a few files were copied to the pen drive before the copy operation hung. So I cancelled the copy operation.

Now I am unable to use the pen drive. I DON'T REALLY NEED ANY FILES THAT I COPIED TO THE PENDRIVE. I JUST WANT TO USE THE PENDRIVE AGAIN.

I have tried using Ubuntu to format the pen drive. But when i use fdisk to delete the partition, it looks like it is working fine but in fact it does not delete the partition. Also I am unable to format it with any other file system.

When I tried to use gparted, it throws the following error:

Error mounting: mount exited with exit code 14: The disk contains an unclean file system(0,0).
The file system wasn't safely closed on window. 
Fixing ntfs_attr_pread_i:ntfs_pread failed: Input/output error 
Failed to read NTFS$Bitmap:Input/output error 
NTFS is either inconsistent, or there is a hardware fault, or it's a softRAID/FakeRAID hardware. 
In the first case run chkdsk /f on Windows then reboot into windows twice. 
The usage of  the /f parameter is very important!. 
If the device is a SoftRAID/FakeRAID then first activate it and mount a different device under the /dev/mapper directory, (e.g. /dev/mapper/nvidia_eahaabcc1). 
Please see the dmraid documentation for more details

When I searched the Internet I found help on how to recover. But I don’t want to recover, I want to format it again.

When I pressed w after deleting the partition, it took more time than previously. After that i removed the pen drive and re-inserted, but the partition I had deleted was still present.

If I simply type the command fdisk /dev/sdb without removing the pen drive after the partition is deleted, then it returns the error message Unable to open /dev/sdb.

Here are the steps that I followed:

root@yesuraj-ubuntu:~# fdisk /dev/sdb 
Command (m for help): d 
Selected partition 1 
Command (m for help): w 
The partition table has been altered! 
Calling ioctl() to re-read partition table. 
Syncing disks 

THE DEMESG PRINTS ARE AS FOLLOWS,
[ 6139.774753] usb 2-1.3: reset high speed USB device number 4 using ehci_hcd
[ 6154.816941] usb 2-1.3: device descriptor read/64, error -110
[ 6169.968908] usb 2-1.3: device descriptor read/64, error -110
[ 6170.158427] usb 2-1.3: reset high speed USB device number 4 using ehci_hcd
[ 6185.200638] usb 2-1.3: device descriptor read/64, error -110
[ 6200.352572] usb 2-1.3: device descriptor read/64, error -110
[ 6200.542093] usb 2-1.3: reset high speed USB device number 4 using ehci_hcd
[ 6205.559460] usb 2-1.3: device descriptor read/8, error -110

I used the dd command and it erased the partition table.

But now when I connect the pen drive, dmesg contains this error message:
[88143.437001] sdb: unknown partition table.

I am not able to create a partion using fdisk /dev/sdb. The error message says that it is unable to find the node.

Other messages from dmesg follow below.

[87100.531596] usb 2-1.3: new high speed USB device number 39 using ehci_hcd 
[87130.915257] usb 2-1.3: new high speed USB device number 40 using ehci_hcd 
[87135.932647] usb 2-1.3: device descriptor read/8, error -110