My wife complained that one of her pen drives stop working and the OS doesn't recognize it any more.
When I check the device I realized that it doesn't have a partition table any more. May be the device is failing. So I quickly create an image of the whole device using dd.
sudo dd if=/dev/sdc of=pendrive.img
I tried fsck.vfat on the image without any luck. Then I found this article. http://www.howtogeek.com/howto/15761/recover-data-like-a-forensics-expert-using-an-ubuntu-live-cd/
The magical tools are, testdisk, photorec, and foremost. Very importantly it all comes FREE with Linux.
I manage to recover most of her important files with these tools. Many thanks to the creators of these software!