First, I would suggest a repair of Avast and REBOOT.

Can you delete the ZA rules for your web browsers and for anything related to avast? After deleting the firewall rules, they should be re-created (“learning mode” or equivalent) when avast and the web browsers try to connect.

If you try to open “about:blank” (as oppose to some link / url), is this problem also happening?

Can you reset to default the settings for IE?

I would also recommend, at least for testing purposes, to disable ZA (but in case the firewall is involved, I’m not sure if a “simple” disable of the firewall would be enough).