An Error Message (-50)


I have been trying to save my files from desktop to a mini-cruiser (one of those small zip drives that plug directly into the USB and are so small you can just wear around your neck). I have had no problems with this in the past, but recently I when I try to transfer whole folders, with multiple files, I get a pop-up box that says "Sorry, the operation could not be completed because an unexpected error occured (Error code -50)". I looked up what the error code means, which is: paramErr - Error in user parameter list. I was wondering what this means and if you have any ideas on how to solve the problem. Thanks for any advice.