USB write protected?

Hi, I have a problem with a brand new USB stick, PNY 64GB I bought on e-bay about two months ago. It started working properly, I transferred on it about 20GB of my photos. I did not notice anything weird. The pictures were there and I think I could even move them on and off, like copying and deleting. After few days, when I wanted to erase them, there was a message that the device is write protected. USB? There is nothing to switch it for write protection like on SD cards, for example.
From that moment, the device once was recognized as inserted in the PC, other times it was not. I could not delete the images, I could not format the device and even the KillDisc software, after running nearly 5 days without a break could not sort this out. There was an error message at 99% of process and I could do nothing else than to skip it, which resulted in the problem persisting on the USB.
Now I cannot even view the files, despite after this treatment I could have seen them few days ago. The files, after I clicked on them, showed mostly unaffected photos in the views, but when I wanted to see any particular photo, all of them appeared to be damaged - there was a grey area on the majority of the photo, just a thin area of the original picture could be seen on the top of the picture.

I have contacted the seller with this problem and they offered me the refund or replace, even assured me that the item will go to the manufacturer.
However, I guess that there are phishers outside just waiting for items like this, who are able to get to the data and do with them whatever they want. I would love to receive a refund but I do not want the USB stick to go out in this condition.

Just to say, that my PC appears to be clean of any malware, I have updated Windows antivir and firewall and I have permanently switched on the paid version of Superantispyware, which scans the PC almost every day and I remove any cookies that appear as a thread. I have no problems with other USB connected devices, even in the same slot...

What would you recommend in this case?
And how to reply to the seller that I am not that adventurous sending out the device in this condition. I offered to them that I would actually physically damage the hardware and post it to them so that they can be sure that I am not trying to fool them by claiming a faulty item while it would be perfectly fit just to get the refund.
They did not make any statement about this idea at all.

PS: after checking some of your answers to a similar problem (such as computer, device, right click, properties, etc) I cannot see the "Security" tab in it. And the disc appears to be full - perhaps after the KillDisc treatment...

PPS: right, while waiting for a reply, I played with it and found out that if I click right on the computer, there is the Security, but previously I did this with the device I want to treat...

Hi,

If I understand you, you wish to remove all the photo's/data on this stick prior to returning it to the seller. Is that correct?

Regards,
Golden

Hi,

OK, we can try to wipe the USB using the Windows DISKPART CLEAN ALL utility. Plug the USB into the computer, and then follow these steps, then post back as we progress.

1. Click the Start
2. In the search box, type cmd
3. In the list that opens, right-click on cmd.exe and choose the 'Run as administrator' option
4. In the cmd window that opens, type the following, hitting enter after each command:

diskpart
list disk

Post back what is written in the window, or better still take screen capture image and attach them to your reply.

Screenshots and Files - Upload and Post in Seven Forums

Regards,
Golden

Hi,

Yes, that's OK. Now type the following in that same window and hit enter:

select disk 2

Then post back another screen capture image so we are 100% sure we are going to wipe the correct disk - we don't want to wipe the wrong disk!

Regards,
Golden

OK.

In that same window, type and following and hit enter:

clean

After a few seconds it will complete. Now go into Windows Explorer, and check to see that the USB drive is empty.

I'm not sure that will fix the problem - you could use it for a bit and see if it works OK.

Regards,
Golden