Quick update. I ended up reinstalling Avast without webshield. It's still working fine. So I have Avast without webshield + comodo firewall and everything is a-ok.
I just uninstalled Comodo AV but left the firewall running. I'm going to reinstall Avast without the webshield and see if it works because I think I forgot to disable webshield last time I tested it.
I had this problem as well. I got a brand new dell laptop in late January. I uninstalled the mcaffee antivirus that came with the laptop and installed Zone Alarm and AVG. After that the browsers would sporadically stop working. I ended up uninstalling everything and just used the...