How to Unblock a Port

By Herman Cruz

Unblocking a port lets you use all the features of a service that uses the port.
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A port enables your operating system to establish a connection with other servers. For instance, AIM chat uses port 4443, games such as "World of Warcraft" use port 3724 and port 25 is the default port to send and receive emails. There are two types of protocols a port can use; the TCP protocol enables you to exchange streams of data through the port and the UDP protocol sends data over an IP network. If a website you want to access uses a port blocked by your firewall, you'll need to add this port to the firewall's exceptions list to unblock it.

Click "Start" and choose "Control Panel" from the Start menu.

Click the "Security" link, click the "Windows Firewall" link and then click the "Allow a program through Windows Firewall" link displayed on the upper-left side of the Windows Firewall box.

Click the tab saying "Add port" found at the bottom of the box.

Type the name you want to give to the port in the "Name" text field, type the number of the port you want to unblock in the "Port number" text field, and beside where it says "Protocol" check the check-mark that corresponds to the type of protocol the port uses (TCP, UPD). If you are unsure about the type of protocol the port uses, you can select both protocol options.

Click the "OK" tab and the port you entered will be unblocked. Your operating system is now able to communicate with the server using the port you entered.