Sorry to hijack this somewhat old thread now, but I just read your post AFTER having bought a new DS708 and having registered it, and updating the system as suggested.
From your many posts I've been reading, you are a old hand at the DS708, so as a newbie, I solicit your advice for a long and happy relationship with my new, though obsolete unit.
So it's too late to follow you advice above, so what is the BEST thing I can do at this point?
So, to review, I unboxed my unit and tried to hook up to WiFi to register, but my unit wouldn't do it, I tried Ethernet and while I could get onto the Internet (weather, sports, news, etc), but when attempting to register it only showed "500 Server Error Cannot Connect." So I went to this sire, and registered w/ my Model/Serial/Password/Username and after about 20 minutes, my unit magically allowed me to connect via ethernet, recognized me as a registered user, and allowed me to update, unfortunately on my factory supplied 8gb SD Card (I should have used a new card and kept the original one as a backup I now learn).
So what is the best way to accomplish this going forward after missing my first best chance at it.