Windows XP Service Pack 2 Firewall
A firewall is a device that protects a computer from some types of malicious network activity. Firewalls restrict certain types of network traffic, for example, blocking attempts to read files on your hard drive. Firewalls may also keep logs of network activity that might be useful if someone attempted to break into your computer. A firewall should be used to protect any computer connected directly to the Internet or any other public or untrusted network.
Microsoft® Windows® XP has built-in personal firewall software, called Windows Firewall, which can be enabled independently for each network interface in a computer. In a home environment, Windows Firewall should be enabled on any connection that leads to the Internet, for example, a modem or network card used to connect to a Digital Subscriber Line (DSL) or cable modem, and should be disabled on devices that are only used to connect to other systems in your home. In a business or school, a network administrator needs to decide which systems need to be protected with a firewall.
The Windows Firewall is enabled by default for all network connections. If you are having network problems, check to see if a firewall is blocking the network activity.
The steps for Windows XP Home and Windows XP Professional are the same.
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