Every time I click new tab in IE8, Avast’s web shield reloads. Is the problem from Avast! or is the problem from IE8?
If in the new tab you’re opening a site (like your default or home site), it’s ok, avast WebShield is scanning it as any other site. I don’t see a problem here.
What exactly do you mean with “the web shield reloads”?
Where do you see this?