Windows Firewall Notifier is a free program which can help block outboard connections through the Windows Firewall. Unfortunately, Microsoft's firewall in Windows isn't necessarily capable of letting you know when something is happening and thus this program can give you more control.
This program is fully portable, meaning that installation is not required. Once running, Windows Firewall Notifier will activate the built-in firewall and initially block connections until you allow them.
Version 188.8.131.52 is a freeware program which does not have restrictions and it's free so it doesn't cost anything.
Virus and Malware Tests: The program has been tested with several antivirus applications and has tested clean of viruses, malware or trojans.