soft ware unable to update, But I can run Internet Explore fine.

[CADMANDO48]

I'm using Win Xp and program so far unable to access to Internet Norton Antivirus 2009, Google earth and Equest Energy simulation.
Internet Explore work fine, I just can't get Norton Antivirus to update. I get Unable to connect to Norton Live update server. Please check your internet connection.”
I use Google earth and that I'm unable to use as well. I use Equest an Energy Simulation and it will not access to it server to run its simulation.
I just know enough about the PC to get by. I believe it is the Proxy setting but then I don't know. I can surf the Internet fine. I even have the windows Firewall turned off and exception select to the programs. I'm at a lose to what the problem is?
Can anyone help!
 

[JJ 3000]

How long has this been happening?

Did you make any changes right before this started?

[CADMANDO48]

I got a new dell Vostro 420 few months back and my Boss uninstall its Virus program and installed Norton Antivirus 2009. And scents day one when Norton was installed I was unable to update Norton virus def. So I was having to more work to bother with it at the time and now I have time. The error I get is “Unable to connect to the Norton LiveUpdate server. Please check your internet connection."
I tried to install Google Earth and it will not install. I was able to download the beta ver. This is the error I get “Installation failed. Ensure that your computer is connected to the internet and that your firewall allows googleupdate.exe to connect and then try again. Error code =0x80072efd.”  and it will I also use Equest an Energy model simulation program. I created the a model But trying to run the Simulation it goes out from the some web site to get the weather info to run the simulation. Says there is no connection. But I can go on line and surf the Internet.
Firewall is off and all programs I'm having problems is in the list to Exception.
My old Dell worked fine. I looked at the setting in Window Internet Explorer to compare the setting for my old Dell. The setting where the same.

[JJ 3000]

Uninstall Norton.