Installing AVAST home lost IE connectivity to internet

I have a fairly new Fujitsu Lifebook running Vista. Last week, the pre-installed demo copies of Office 2008 and Norton AV both expired. I had CD’s for Office pro 2003 and I downloaded the Avast Home installation file using IE. I then de-installed both of the expired tools, Office 2008 and Norton AV. Next, I installed the Office 2003 and the Avast Home AV. Then after a re-boot, Avast did a full boot scan. Following another reboot, I then tried to connect to the internet using IE and I was told I have no Internet connection by IE. The Avast Home AV is also unable to connect to get updates from the installation version to current version. When I de-installed Norton AV, I had been prompted to turn on Windows firewall, which I said Yes to. I suspected the firewall as possibly causing the internet connection problem, so I turned off the windows firewall. After another reboot, still no internet connection according to IE. I then decided to try to avoid the wireless connection to my router (I have a cable modem and router, no firewall). I got out an ethernet cable and plugged the Lifebook PC directly into the router. The network tools on Vista can see the internet. The properties show packets being sent and received. From a command prompt window I can do a
PING GOOGLE.COM
and I get ping replies back from google, showing I do have an internet connection, although IE still cannot see the internet connection. What can be blocking the type of packets used by IE when the windows firewall is turned off??? I went back to the firewall settings and it still shows it being off.

HELP!!!

Download and run the Norton Removal Tool.

Uninstall avast! by going to Add/Remove Programs

Download and run avast! uninstall utility.

Reinstall avast!