To Block a specific port on Windows 7 (assuming you are using windows firewall) . Go to control panel, Select Administrative tools, Select Windows firewall with advanced security, Click on Inbound rules, click on "New Rule" in Action Pane, Click on Port then next, enter port then next etc. and you will create a new rule that will block access to the port you specified (it will be added to the list of rules currently displayed governing inbound traffic to your computer). You will find it in the list under the name you called it when you created it.