I frequently get asked if Microsoft's Windows Firewall is a good firewall. Here's my response:Windows Firewall works well as an inbound firewall, but it does not do outbound blocking. It's free with Windows and worth every cent. It does work. I took off ZoneAlarm, Tiny Firewall, and McAfee host-based firewalls about two years ago to see if Windows Firewall works. I do a lot of traveling and my multiple laptops are exposed to malicious code and hackers all the time. The result?After two years, no hackers or malware got by it. It does what it claims to do. With that said, it is a very basic firewall and many other firewalls, including ZoneAlarm do a much better job. On the positive side, it doesn't interfere with or slow down legitimate operations nearly as much as the other firewalls.Here are Windows Firewall deficiencies:-Inbound blocking only-No alerting-No signature recognition of attacks (i.e. a port scan will never be identified as a port scan in the log)-Crappy log file format (hard to read and understand for the beginner-Max log size is 32 meg.-No way to copy log to another place without turning off firewallWith all of this said, Microsoft's Windows Firewall does work at what it says it does. It's a great firewall for people who would never install another firewall.