Using Windows Firewall

Microsoft regularly releases improvements to Windows to help keep you protected from constantly changing Internet threats. Windows Firewall is one such improvement, first released as part of Microsoft Windows XP Service Pack 2. If you have Automatic Updates enabled, Windows Firewall is already protecting you.
Windows Firewall protects your computer by blocking communications that might actually be dangerous software trying to find a way to connect to your computer, rather than communications from a person or program you want to interact with. Windows Firewall is smart enough to allow connections from computers in your home and to block those connections from computers on the Internet. For example, Windows Firewall will allow you to share files or a printer between two computers in your home, but it will block any attempts from people on the Internet to connect to your computer.
You only need to configure Windows Firewall if you are having a problem with a program connecting to the Internet. If you’re not having a problem, simply verify that Windows Firewall is enabled on your computer, and enjoy using the Internet knowing that Windows Firewall is helping to protect you. If you are experiencing a problem, you can add a firewall exception for that program to ensure Windows Firewall isn’t causing the problem.

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What Windows Firewall does—and does not—do

Windows Firewall does offer some protection from network attacks from malicious software known as worms. However, Windows Firewall does not protect you from viruses or spyware. For more information about antivirus and antispyware software, read Protect your network from viruses and malicious software.

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Verify that Windows Firewall is enabled

To verify that Windows Firewall is protecting your computer

1.	Click Start, and then click Control Panel.
2.	From the Control Panel, click Security Center. • If Windows Firewall shows On, you are protected. • If Windows Firewall shows OFF, it has been disabled. If you have another firewall installed, this is probably OK. If you don’t have another firewall installed, you will need to re-enable Windows Firewall from within Security Center.

To re-enable Windows Firewall

1.	Click Recommendations.
2.	Click Enable Now.
3.	Click Close.
4.	Click OK. Now Windows Firewall will protect you from many unwanted communications.

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Add a Windows Firewall exception

Sometimes Windows Firewall might block a program that you use from connecting to the Internet. If you are experiencing a problem with a program that can’t connect to the Internet, but you are still able to browse the Web (demonstrating that it’s not a general problem with your Internet connection), you can add a Windows Firewall exception for the program that’s having problems. This will allow you to use that program without Windows Firewall blocking it.
To add a Windows Firewall exception

1.	Click Start. Click All Programs and find the program that you want to add an exception for. Then right-click the program and click Properties.
2.	On Shortcut tab in the Properties dialog box, right-click the Target box, and then click Copy. This copies the program’s location to your clipboard.
3.	Click Cancel to close the Properties dialog box.
4.	Click Start, and then click Control Panel.
5.	From the Control Panel, click Security Center.
6.	From the Security Center, click Windows Firewall.
7.	On the Exceptions tab, click Add Program.
8.	In the Add a Program dialog box, click Browse.
9.	In the Browse dialog box, right-click the File name box, and then click Paste.
10.	Click Open.
11.	Click OK.
12.	Windows Firewall adds an exception for your program. Click OK again.

Now, Windows Firewall will allow your program to communicate with other computers on the Internet.