After install Avast PRO4 not have access to internet.MI computer is Windows XP Professional SP3 with 3G USB modem connection. I Firewall Windows.Uso IE7 and Mozilla Firefox latest version. Bitdefender antivirus and had Kaspersky, but when it comes to installation Avast had already uninstalled. I have a Spyware Doctor Firewall.Despues without uninstalling Avast the problem persists.
You may need to change network settings or any other suggestions? Thanks for the help. ???
Something is telling me BitDefender (even as on demand only) is messing something.
Also, it will be good to fully remove Kaspersky.
See: http://support.kaspersky.com/faq/?qid=208279463
Also see http://forum.avast.com/index.php?topic=12079.15