IPod cannot be restored or synced

I plug the ipod Nano into my computer and itunes starts and begins to sync a song and then stops and i get the error message "ipod cannot synced. The required file cannot be found". And "Windows was unable to save all the data for the file G:\iPod_Control\..." sometimes pops up from the windows start bar.

I try to restore through itunes and it gives me the 1439 unknown error message, and sometimes (-48) error message.
I have the lastest version of iTunes installed. I have restored my iPod a few times -now it won’t even let me restore (error -48)-. I have tried plugging it into other USB ports, I have tried restarting my PC, I have checked errors on the device.. Nothing’s working