internet is connected but i can't view websites. What do i do?

After I got Avast!, my internet explorer stoped letting me view websites. I know my internet is still connected because I can still Go on my instant messenger. Right now i’m on my laptop, the problem is on my home computer. Can you tell me what to do?

I have windows Vista on the computer and it is all up to date. The version of Avast! i have is 4.7 and the virus database file version is 00721-2. I do have a firewall on which came with windows but even when i turn it off i still cant go on websites. The computer also came with McAfee but i dont think that its interfereing but i dont know.

Everything was working untill I got Avast! is there anything I can do or do I have to uninstall it?
Thanks

Are you sure this is in the correct forum ‘avast! Distributed Network Manager’ ?

Check that you haven’t blocked ashWebSv.exe in the McAfee firewall.

If you Terminate the Web Shield provider that should allow you to connect, if so it would tend to confirm something (probably McAfee firewall) is blocking ashWebSv.exe.

The is a known problem with WebShield and Vista that seems to be solved soon:
http://forum.avast.com/index.php?topic=26871.msg220268#msg220268

Do you use McAfee with antivirus or just the firewall?