MORE INFORMATION
What is a firewall?
A firewall helps keep your computer more secure. A firewall restricts information that comes to your computer from other computers and gives
you more control over the data on your computer. Additionally, a firewall provides a line of defense
against people or programs, including viruses and worms, that try to connect to
your computer without invitation.
Think of a firewall as a barrier
that checks information, also known as traffic, that comes from the Internet or from a
network. The firewall either turns traffic away or lets traffic pass through to your
computer, depending on your firewall settings.
In Microsoft XP
Service Pack 2 (SP2), you can turn off or turn on the Windows Firewall.
By default, Windows Firewall is turned on for all network interfaces. This
configuration provides network protection on new Windows XP installations
and upgrades. This default configuration also helps protect your computer from new network connections as they are
added to the system.
Although
Windows Firewall is turned on by default, some computer manufacturers
and network administrators may turn it off. You do not have to use Windows
Firewall. You can install and run any firewall that you want. Evaluate the
features of other firewalls, and then decide which firewall meets your
requirements. If you decide to install and run another firewall, turn off Windows
Firewall.
How to configure Windows Firewall settings
Warning This workaround may make your computer or your network more
vulnerable to attack by malicious users or by malicious software such as
viruses. We do not recommend this workaround but are providing this information
so that you can implement this workaround at your own discretion. Use this
workaround at your own risk.
To examine and configure your firewall settings, follow these steps:
- Click Start, click
Run, type wscui.cpl and then click
OK.
- In Windows Security Center, click
Windows Firewall.
Windows Firewall includes the following tabs:
- General
- Exceptions
- Advanced
The
General tab includes the following settings:
- On (recommended)
- Don't allow exceptions
- Off (not recommended)
When you click to select
Don't allow exceptions, Windows Firewall
blocks all requests to connect to your computer, including requests from programs
or services that are listed on the
Exceptions tab. The firewall also blocks discovery of network devices, file sharing, and printer
sharing.
The
Don't allow exceptions option is useful when you connect to a public network, such as one
that is associated with an airport or with a hotel. This setting helps protect your computer by
blocking all attempts to connect to your computer.
When you use
Windows Firewall with no exceptions, you can still view Web pages, send and
receive e-mail, or use an instant messaging program.
The
Exceptions tab lets you add program and port exceptions to
permit certain types of inbound traffic. You can set a
scope for each exception.
For home and small office networks, we
recommend that you set the scope to the local network only, if it is possible.
This configuration enables computers on the same subnet to connect to the program on the
computer, but drops traffic that originates from a remote network.
The
Advanced tab lets you configure the following:
- Connection-specific rules that apply for each network
interface.
- The Security Logging configuration.
- Global Internet Control Message Protocol (ICMP) rules that apply to ICMP traffic. (This traffic is used for error and
status information transmission.)
- Default settings.
How to configure file sharing
For home and small office networks, use the
Network Setup Wizard to configure file sharing. With this wizard, you make sure that the firewall
is configured with the highest security possible. In a typical home network,
all computers are in the same subnet. In such a configuration, we recommend that you configure file sharing only for local computers.
Note To start the Network Setup Wizard, click
Start, click
All Programs, click
Accessories, click
Communications, and then
click
Network Setup Wizard.
For additional information about Windows Firewall, click the following article number to view the article in the Microsoft Knowledge Base:
843090
Description of the Windows Firewall feature in Windows XP Service Pack 2