Firewalls If you use a computer at home, the most effective and important first step you can take to help protect your computer is to turn on a firewall.Firewalls If you use a computer at home, the most effective and important first step you can take to help protect your computer is to turn on a firewall.
Windows 8, Windows 7, Windows Vista, and Windows XP SP2 or higher have a firewall built-in and turned on by default. (Note: Support for Windows XP ended in April 2014.)
If you have more than one computer connected in the home, or if you have a small-office network, it is important to protect every computer. You should have a hardware firewall (such as a router) to protect your network, but you should also use a software firewall on each computer to help prevent the spread of a virus in your network if one of the computers becomes infected.
If your computer is part of a business, school, or other organizational network, you should follow the policy established by the network administrator.