how to block and unblock a program with windows firewall in windows 7

Hi friends !! In this post I will explain how to open Windows Firewall in Windows 7 and Windows Vista. What are ports. How to block and unblock particular program

To open Windows Firewall go to

Choose Start > Control Panel > Security >Windows Firewall.

Or

Press Windows logo key+R; type firewall.cpl and press Enter.

or

Choose Start, type windows firewall in the Search box, and then select Windows Firewall in the results list.

or

In Security Center, click the Windows Firewall link (in the left pane).

1. Click Turn Windows Firewall On or Off .If a security prompt appears, type an administrator password or confirm the action.
2. Click On or off; then click OK 

 Testing for online vulnerabilities

Traffic flows in and out of your compute through ports—small, authorized doors in the firewall. (These ports aren’t the same as the hardware ports that you connect devices to.) A port number identifies each port uniquely, and certain ports handle only a specific type of traffic. Port 80 is used for HTTP (web) traffic, for example. Other ports allow instant messages, printer sharing, and so on. (You can find others by searching the web for “well-known ports”.)

Windows Firewall leaves some ports open by default (File and Printer Sharing and your local network connections, for example) but blocks most of them to incoming traffic, so when a new program wants to get online, the firewall displays a dialog box asking you whether it’s OK

_ Unblock if you recognize the program name. The firewall opens the relevant listening port for this connection and

    Future incoming connections. If a security prompt appears, type an administrator password or confirm the action.

_Keep Blocking if you don’t know which program the firewall is asking about, or if you know it but don’t want it  Phoning home. The program might not work properly if it 

 can’t accept incoming traffic (desirable in some cases).

Windows Firewall Tip:

You can check Block All Incoming Connections to block all unsolicited incoming traffic, even traffic that normally would be permitted by an exception (described next). Use this extra-secure mode when you connect to a public wireless hotspot in a café, airport, or hotel, or when a virus is spreading over your network.

5:40 PM