In windows 7 , 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.You can following the below steps to customize turn of or turn off windows firewall in windows 7.
1.Click Start Menu and open Control Panel
2.Open Windows Firewall from Control Panel
3.In the left pane of Windows firewall windows, click Turn Windows Firewall on or off
4. Now you can turn windows firewall on or off