Firewalls help block unauthorized access to your computer by restricting incoming connections. A firewall running on your computer is a useful security tool, even if you also have a router that acts as a firewall.
Windows Vista
The Vista firewall is on by default. If it has been turned off:
- Click the Start button and choose Control Panel. Click Security.
- From the Windows Firewall section, choose “Turn Windows Firewall on or off.”
- On the right, click “Change settings.” Click “On (recommended).”
Windows XP
If you are running Windows XP Service Pack 2, the firewall is on by default. If it has been turned off:
- Click the Start button and choose Control Panel.
- Switch to Classic View and double-click Network Connections.
- Double-click Local Area Network Connection and then click the Properties button.
- Select the “Advanced” tab. Put a check in the checkbox that says “Protect my computer and network by limiting or preventing access to this computer from the Internet.”
Older Windows Systems
A firewall program that works with older Windows systems is called ZoneAlarm and is free for personal use.
Mac OS X 10.6 (Snow Leopard)
The Snow Leopard firewall is off by default. To turn it on:
- Choose System Preferences in the Apple menu.
- Click the Security icon.
- Click the Firewall tab and click the Start button. If the button says Stop, your firewall is already running.
Mac OS X 10.5 (Leopard)
The Leopard firewall allows all incoming connections by default. To restrict incoming connections, see Apple’s Leopard firewall information and instructions.
Mac OS X 10.2, 10.3, or 10.4 (Jaguar, Panther or Tiger)
The firewall is off by default. To turn it on:
- Choose System Preferences in the Apple Menu.
- Click the Sharing icon.
- Click the Firewall tab and click the Start button. If the button says Stop, your firewall is already running.
Mac OS X 10.1 (Cheetah or Puma)
Mac OS X 10.1 includes the command line program ipfw. If you are unfamiliar with command-line tasks in the Terminal application, and you’re not using a router or other hardware firewall, Cruzio recommends upgrading to a newer system.
Mac OS 9 or earlier
Firewall software is not included with the system. If you have OS 9, and you’re not using a router or other hardware firewall, you may want to protect your computer by turning off file sharing.