How to Turn On Windows Firewall

Method 1 of 3:

Open Start. Click on "Search". Type "firewall" into the search box. Select "Windows Firewall" from the result list.
Select "Turn Windows Firewall on or off" in the left pane. Enter your administrator password if you are prompted for one.
Click "Turn on Windows Firewall" in the network locations you wish to protect. Click "OK" to confirm the change.
1. You can also select the "Block all incoming connections, including those in the list of allowed programs" check box if you want Firewall to block all programs.

Method 2 of 3:

Open the Start menu and select "Control Panel."
Select "Security" and then click on "Windows Firewall."
Click "Turn Windows Firewall on or off." You may be prompted to enter an administrator password.
Select "On (recommended)," then click "OK" to confirm the change.
1. Select the "Block all incoming connections" check box to have Firewall block all programs, even those on the "Exceptions" tab.

Method 3 of 3:

Open the Start menu.
Click on "Run" and type in "Firewall.cpl" in the box. Click "OK."
Select "On (recommended)" in the "General" tab. Click "OK."
1. In some cases, the "On (recommended)" option might be grayed out. It may be because a third-party firewall is already in use on the system. Turn off the third-party firewall to activate Windows Firewall. Make sure to consult with your system administrator before hand, if you have one.