Almost always this is the result of a misconfigured firewall. You're going to have to figure out which one it is and then how to rectify the problem.
I have a 2 month old laptop, HPdv9910. It came with Norton Antivirus. Vista.
I decided to try something else. However, every antivirus program I have tried says "we can't download your software because we're having trouble accessing the internet". I've tried AVG Free, ZoneAlarm (of which I paid $49 for), and Mcafee. What is the problem? I've called HP and they are no help. I'm able to surf the internet and download other stuff just fine. Any advice anyone?