I setup my work PC for a dual boot system and joined it to our domain. When I first started using Vista everything seemed ok. It checked for updates for about 2 weeks and everything was good. Then out of the blue it keeps getting the error saying unable to check for updates. Nothing changed on our network. All of the Vista help says check your personal firewall and be sure to allow Windows update site through. I do not have any software firewall installed on the system. Now I am finding out that I have a customer that is having the same issue.