I found a solution in a post on the web somewhere, and it seems to be working. I have a backup running (apparently normally) right now. I have verified that a backup set is being created on the mapped drive and that I can access it, but obviously I have not yet verified that I can restore from it. First, do not attempt to set up any users on the DNS-321 using the web interface. When I did that it just made matters worse re being able to access the NAS from Vista at all. Eventually I went back and reset the NAS to its defaults, using the button on one of the web interface pages (I forget which one). This restored the original situation where anyone accessing the NAS has full read/write privileges. When Vista backup asks for a password to log onto to the DNS-321 use "EVERYONE" as the username. I used the same password that I use to log on to the computer, but according to the post I got this tip from, any 5 - 8 character password should work. Now that I seem to be actually accomplishing what I bought the unit for, I am much happier with the product. A little better documentation and / or technical support would be nice though. You can't believe the hours and frustration I went through to get to this point.