Irish having a firewall close those ports shouldn't stop Norton or Windows from updating, all the ports on my machine come up on shields up as stealth but I can still get the updates without any trouble. I did have problems with the XP firewall conflicting with Zonealarm but that's probably my fault so I shut it off. It seems like this new monster uses file&print sharing to start it's dirty work so unless you really need it disabling it is a very good idea.