Best Free Firewall

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Comodo Firewall      Its Defense+ HIPS performance exceeds commercial products and leads the class, it includes an excellent "memory firewall" feature, and it allows you to quickly switch between Defense+ security modes and configurations. Includes automatic updates. Installation can automatically configure your PC to use the Comodo SecureDNS (but you can do this without installing CIS).  [Revising] http://www.comodo.com/ http://www.comodo.com/home/download/download.php?prod=firewall 34 MB  5.3.181415.1237 Unrestricted Freeware    Windows XP (SP2), Vista, Windows 7 64-bit version available (use the download link and select 64-bit Windows from the drop down box) Additional Features of Interest (as Found in its Interface): Installation mode/training mode, auto updating, built-in help and tips, parental control with password protection, extra themes and languages, and a stealth ports wizard. Purges old or unused firewall/Defense+ policies or unused files (safe files, files waiting for review, etc.). Displays balloon messages for instant logging events. To learn more visit its forum, online help, or release notes.

Why use our Firewall? Comodo Firewall Pro introduces the next evolution in computer security: Default Deny Protection (DDP™). What is DDP? Most security programs maintain a list of known malware, and use that list to decide which applications and files shouldn't access a PC. The problem here is obvious. What if the list of malware is missing some entries, or isn't up to date? DDP fixes this problem to ensure complete security. The firewall references a list of over two million known PC-friendly applications. If a file that is not on this safe-list knocks on your PC's door, the Firewall immediately alerts you to the possibility of attacking malware. All this occurs before the malware infects your computer. It's prevention-based security, the only way to keep PCs totally safe. Firewall is a component of Comodo Internet Security 2011, which comes bundled with Comodo Antivirus. You have the option to only install Firewall if you prefer. Firewall is also a part of Comodo Internet Security Pro 2011, which gives you the most robust defense and inlcudes other components like WiFi security, live 24/7 expert assistance for numerous computing needs.  Firewall Features: Easily understood and informative alerts No complex configuration issues—perfect for amateur users Lots of configuration options let techies configure things just as they like DDP-based security keeps you informed and PCs safe Quickly learns user behavior to deliver personalized protection User-friendly, attractive graphical interface One of the first steps in securing a computer is downloading and activating a quality firewall to repel intruders. Only this free firewall software has access to Comodo's extensive safe-list of PC-friendly applications, a key component of Default Deny Protection™. Check out our firewall software today or upgrade to 360-degree protection with Comodo Internet Security Pro 2011.  Online Armor Free    Excellent proactive security performance. Includes a "run safer" feature to reduce rights for specific risky applications, and the ability to monitor key logger activity and host files. It handles the installation of new programs better than many other tested products. It doesn't have automatic updates or a built-in help. It's mandatory to enter an email during installation, and it has a pre-checked option to send it anonymous information. http://www.online-armor.com/ http://www.online-armor.com/downloads.php 19 MB   4.5.1.43  Restricted Freeware   Windows XP, Vista, Windows 7 (32-bit only) Additional Features of Interest (as Found in its Interface): Set passwords, protect programs (right-click > "Advanced options"), key Loggers tab/Hosts tab, and multi desktop support. To learn more visit its forum, and blog.

Zone Alarm Free Firewall 2010     Top security performance, setup is easy for any experience level,  popup alert format is easy, customizable settings, anti-phishing protection, identity theft protection, online backup (2 GB), solid inbound/outbound os firewall, hosts file lock, stealth mode, and more.  Free version has inadequate protection against interactivity behavior of installed software. Programs can still reach the internet using browser even when program is blocked from internet access by Zone Alarm. No High setting for program access in Free version. In spite of available automatic update option, updates almost always must be performed manually. http://www.zonealarm.com/security/en-us/zonealarm-pc-security-free-firewall.htm http:///www.zonealarm.com/security/en-us/anti-virus-spyware-free-download.htm 44.8 MB    92.102    Restricted Freeware    Windows XP (32-bit only), Vista, Windows 7 64-bit compatible on Vista and 7 (designed for both 32-bit and 64-bit) Not compatible for XP 64-bit  To learn more visit its service and support page

Outpost Firewall Free     Proactive security (at max settings) compares with Online Armor. Highly flexible protection, simplified alert messages, and includes a full screen mode. It fails tests for protection against malicious logouts or system shutdowns. The free version lacks automatic updates and the ability to break active connections. http://free.agnitum.com/ http://download.cnet.com/Agnitum-Outpost-Firewall-Free/3000-10435_4-10913746.html 16.63 MB    2009    Restricted Freeware    Windows 2000, XP, Vista 64-bit version (98.81 MB v 7.1) available here:  http://download.cnet.com/Agnitum-Outpost-Security-Suite-Free-64-bit/3000-18510_4-75328026.html Reduced HIPS monitoring (lacking anti-key logger protection for example) Additional Features of Interest (as Found in its Interface): Built-in "Help", full screen mode or entertainment mode.

Privatefirewall    Effective proactive security and stealth, one of the lightest of all tested firewalls on memory, simple setup (no nags or ads!). Easily choose between 3 network profiles. Has a unique "email/system anomaly detection" feature, which trains over 7 days by default. Ineffective self-protection, fails a leak test (see echo2), and fails some tests for prevention of malicious system shutdowns. It doesn't have an automatic installation mode (but it has a training mode in "Settings" > "Advanced"). The tray icon flashes for log events instead of network activity per se. No update feature. http://www.privacyware.com/ http://www.privacyware.com/personal_firewall.html 7.6 MB   7.0.23.3  Unrestricted Freeware    Windows 2000, Server 2003, XP, Vista, Windows 7 (32/64 bit*). 64-bit compatible Additional Features of Interest (as Found in its Interface): Built-in help and tips. Auto trusts safe vendors. Able to block outbound email automatically. Network options for experts, with three default settings to modify (Home, Public, Work). To learn more visit its feature list and online support (change log, user guide, tutorials).