Enabling your firewall can help prevent hackers or malicious software (such as worms) from gaining access to your computer through a network or the Internet. A firewall can also help stop your computer from sending malicious software to other computers.

Enable Windows Firewall on Vista / Windows 7:

• Click the 'Start' button and select 'Control Panel'.
• Select the 'Turn Windows Firewall On or Off' option.
• In both the Home Network and Public Network sections, check the 'Turn Firewall On' option.
• Click 'OK'.

Enable Windows Firewall on Windows XP SP2:

• Click the 'Start' button and select 'Run'
• Type Firewall.cpl and click 'OK'
• On the General tab, click 'On'.
• Click 'OK'.