I have a 4gig flash drive, which I can read from but not write on, erase, nor format in any computer (tried in 7 different computers including xp, vista, and win7).

I want to erase all the data inside because it is useless. Once I erase something, it erases it and gives me an error that it can't find the file. Once I refresh the folder, the file comes back. I tried holding Shift + Del. I also tried to use the command to format it in safe mode, but it says "access denied". I don't have a write protection button or whatever it is on my flash drive. It's just a simple small 4 gig one.