Comodo Firewall with Windows XP SP2 is a top Firewall "built from the ground up unlike some personal Firewalls that are cut down versions of industrial Firewalls".
For a free Firewall Comodo on XP is a very good security application, not a system hog and has quite a small footprint, incoming and outgoing can be controlled 100% (unlike XP Firewall) its interface is easy to use and configure, if your running XP and want a safe strong clean Firewall Comodo Firewall will work very well "and its free, Updates and upgrades are also free".

Note this is the same Firewall that is Vista compatible

Link > Comodo Firewall v3

More on Comodo with Vista soon here

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