What does this mean when I am Restoring?

Question

I have tried all the five 'R's of troubleshooting. When I get to the Restore part in iTunes, it tells me "There was a problem downloading the ipod software for the ipod 'iPod'. The requested source was not found."
Does anyone know what this means? I have a 4th or 5th Generation iPod with the click wheel.
It also makes a click click sound while it's plugged into the computer. All my songs have been erased and it does not recognize it in My Computer at all. Thanks so much.
4-5th (2 yrs old)Generation 20 GB click wheel (no color)   Windows XP  

Answer 1

replying to quynh8
Well, in My Computer, it doesn't recognize the iPod at all. I think it's dead. THANKS FOR YOUR HELP!! :)
let's keep pursuing Yin's suggestion. sometimes an ipod won't show up in Disk Management unless you put it into disk mode first. if you put her into disk mode, does she show up in Disk Management?
Putting iPod into Disk Mode
... for a little more information on the possibility that Yin is checking on (a Windows drive letter confusion), see the following document:
Windows confuses iPod with network drive or hard drive and may keep iPod from mounting or songs may seem to disappear
(you aren't getting the classical symptoms of a drive letter confusion, but it's worth checking on.)