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Free Firewalls

Free Firewall w Fprot
Running on all Windows versions, this security software package enables you to protect your personal data at home, without complicating your working enviroment or putting too much strain on your computer's resources. F-Prot Antivirus for Windows includes, among other things, an Updater to keep your protection up-to-date, a RealTime Protector that constantly keeps an eye out for your data and a Scheduler to schedule the routine tasks of scanning your system.

Free Firewall w Kerio
For home users, Kerio Personal Firewall 4 is available in two flavors - the full edition and the limited free edition. After installation, KPF works as the full edition for 30 days, after which it becomes the limited free edition. Limited free edition does not provide the content filtering capabilities such as blocking pop-up windows, ads, VB scripts, cookies, etc. and other extra features. Please see the comparison table for more details.

Free Firewall w Outpost
The free firewall version of Outpost Firewall offers a basic protection solution for casual web surfers and low budget systems.

Comodo Firewall
Unfortunately, most firewalls leak. But Comodo Firewall has passed all known leak tests to ensure the integrity of data entering and exiting your system. Comodo has put their firewall through all kinds of tough tests to ensure their firewall is strong enough to prevent such attacks right out of the box.