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A firewall helps protect your computer from hackers who might try to delete information, crash your computer, or even steal your passwords or credit card numbers. Depending on which operating system you have on your computer, you might already have a firewall and it might already be turned on for you.
A firewall is included in most Windows operating systems. To turn on or check your firewall settings, click the link that corresponds to the operating system you use.
Windows 7 comes with Windows Firewall, a two-way firewall that is automatically turned on. It's as powerful as the firewall in previous versions of Windows, but now it's more flexible and easier to use. For more information see Windows Firewall.
Note You do not have to use Windows Firewall—you can install and run any firewall that you choose. Evaluate the features of other firewalls and then decide which firewall best meets your needs. If you choose to install and run another firewall, turn off Windows Firewall.
Windows Vista comes with Windows Firewall, a two-way firewall that is automatically turned on.
You do not have to use Windows Firewall—you can install and run any firewall that you choose. Evaluate the features of other firewalls and then decide which firewall best meets your needs. If you choose to install and run another firewall, turn off Windows Firewall.
Windows XP SP3 and Windows XP SP2 come with Windows Firewall automatically turned on. For more information about Windows Firewall, see Understanding Windows Firewall in Windows XP SP2.
Windows XP comes with Internet Connection Firewall, but you must turn it on to use it.
To turn on Internet Connection Firewall:
Point to Control Panel, double-click Network and Internet Connections, and then click Set up or change your home or small office network.
Follow the steps in the Network Setup Wizard to turn on the Internet Connection Firewall.
When you choose a configuration in the wizard that indicates that your computer is connected directly to the Internet, the Internet Connection Firewall is turned on.
Windows 7, Windows Vista, and Windows Service Pack 3 (SP3) come with Windows Firewall automatically turned on. Visit Microsoft Update to download Windows XP SP3 for free.
For more information about how Windows Firewall works:
Windows 7 Features: Windows Firewall
Explore the features: Windows Firewall (Windows Vista)
Understanding Windows Firewall (Windows XP SP2 and higher)
What is a firewall?
How to choose a firewall
For IT Pros: Windows Firewall
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