I need some advice on firewalls. I have an Intel Pentium 3, 1000MHz computer with Windows XP Pro, SP2. I already have a built-in Windows XP firewall but until last week I also had ZoneAlarm installed. Due to a recent conflict with a critical Microsoft update, ZoneAlarm would not allow me to connect to the Internet so that I could download an updated version. So I uninstalled ZoneAlarm and got my connection. Since I surf the Web often, I would like to know if installing a firewall such a ZoneAlarm would interfere with my Windows XP firewall. I believe one cannot have more than one firewall installed. I'm a little confused, though, because I thought my Windows firewall was always ON even when I had ZoneAlarm. Any help is much appreciated. Can anyone recommend a good firewall, perhaps a freebie?