I was formatting a computer for a client and had my USB Pen sitting in it still, I was at the step where I needed to delete the partitions so I just went through and deleted everything... What I didn't notice was that my USB pen was showing as a drive in the setup screen.
I go through the install, and go to install the drivers that where on my pen when all of a sudden I'm prompted with a "you must format this device" screen. So, I plug it into my computer to move the drivers back over, and windows lets me know that it can't format the drive, because I destroyed the MBR...
So I search online for various methods of restoring my pen when I find a couple of utilities... One will allow me to supposedly backup the MBR and partition from one pen and copy it to mine, and the other will just let me low level format the device.
I give the partition copy a shot, but of coarse since the utility plays with the MBR my virus scanner goes all ape over letting me use it. So, I took the long shot with the low level format.
I went and grabbed the HDD Low Level Format Tool
and fiddled around and sure enough, I now have a working pen drive again...
For anyone in a similar pickle, simply download the above program, click on the drive to format (be sure to do this properly here, otherwise you'll destroy the data on another drive!), select the "low level format" tab and click "Format This Device".
The following screen took about 20 minutes to complete on my 1gb pen, so your mileage may vary.
Once the low level format has completed, just use the Windows Format Disk utility to standard format your device. To do this go to "My Computer", Right Click the device, choose "Format" then do a full (non-quick) format on the device.
Now you're in business!