Windows Vista Firewall acts like a fence between your computer and the outer world, but since any fence needs a gate, you have to let some data get in and out by setting exceptions. While some exceptions are set up automatically by Windows Vista, others have to be configured manually, so follow these steps to allow them manually.
Click Start and enter the Control Panel
Here, click the link called "Allow a program through Windows Firewall" (bellow the Security).
Go to the General Tab, and make sure that the option "On (recommended)" is selected. If not, enable it (this will enable the firewall).
Go to the Exceptions tab at the top.
To add a program you to your exception list click Add Program (near the bottom).
A list with the programs on your computer is displayed. Locate the program, highlight it and click OK.
Be sure that the check box besides your program is checked, then click OK.
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