Well, the funniest thing happened. I did try it on different computers and nothing happened. It was not showing in computer manager either. The problem is gone though. I do not how it was fixed, it just started working out of the blue. These are the steps that caused (maybe) the "fix:"
- I shut down the computer it last worked on and unplugged it. (This trick works when the computer keeps giving the unknown error when the USB stick is inserted... but I figured I'd give it a shot).
- I powered the computer back up and stick the flash drive in and still it did not work.
- I then take it out... then put it back in and voila! - It started working again.
It's been working on all computers ever since. I don't really get why it starts working again, but I am not complaining!