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This article will explain in detail how to find out which ports are blocked by the firewall in windows. The editor thinks it is very practical, so I share it with you as a reference. I hope you can get something after reading this article.

What does a listening port mean?

By definition, a listening port is a network port that a process or application listens on. The so-called monitoring is to receive information through data packets. A listening port is an open port that accepts incoming packets and forwards them to the desired destination application / process.

Listening on a port does not mean that it is allowed by the firewall. The listening port simply means that it is receiving some kind of traffic. However, the traffic can still be blocked by the firewall.

2. Check the listening port

Before checking the blocked ports, let's find out which ports the Windows device is listening on. This is because you think the ports blocked by the firewall are not listening at all, so your application may not have received any packets.

To check the listening port on the Windows computer, start the command prompt and type the following command:

Netstat-a-n

The port whose status is listed as "Listening" is the port that listens for network traffic. You can scroll down the list and find the port you want. Alternatively, you can use the following command to find a specific network port and check to see if it is listening. Replace the PortNumber in the following command with the port number you are interested in.

Netstat-ano | find "PortNumber" | find "LISTENING"

If you see any list under this command, the port you specified is listening. If the space is empty, it cannot find the port you mentioned, or if it does find it, it is not listening.

Check whether the Windows firewall is blocking the port.

1. Use the firewall log to check blocked ports

One way to check for any blocked ports is through the Windows Firewall log. Logs are an important factor in determining firewall behavior. However, by default, the login of packets lost by login (that is, packets blocked by the firewall) is disabled in Windows. These ports must be active, and then you can check the generated logs to see which ports are blocked.

To generate logs for dropped packets, you must first determine the network profile that is currently in use. To do this, open the Network and Internet page (run-> ms-settings:network-status) in the Settings application, and then click Properties under the connected network.

On the Properties page, you will see whether the selected profile is Public, Private, or Domain.

Now that you know the working network profile, you must enable the login feature for dropped packets. Open Windows Firewall in Control Panel by typing firewall.cpl in run, and click Advanced Settings on the left.

On the Windows Defender Firewall with Advanced Security page, click Properties in the right pane.

In the Properties pop-up window, switch to the profile tab you noticed earlier in the Settings application, and then click customize under logging.

In the customize window, select Yes from the drop-down menu in front of record dropped packets, and then click OK.

Click OK to close the Properties window. Now, use File Explorer to navigate to the following location to check the generated log to see which ports are blocked.

C:\ Windows\ System32\ LogFiles\ Firewall

Open a text file named pfirewall.txt and find all blocked ports. If not, the file will be empty.

two。 Use the command prompt to check blocked ports

The command prompt displays the port on which your computer is currently listening. Any ports that are not shown simply indicate that they are blocked by the firewall or are not listening.

Run the command prompt with administrative privileges, and then type the following command:

Netsh firewall show state

Although netsh firewall has been deprecated, it can still provide the required information.

The open port will be given in the highlighted area. Here, you can determine whether the port you are looking for is open.

How to open a blocked port

If you find that the port is blocked by Windows Firewall, you can use the following steps to open the port.

Open Control Panel-> system and Security-> Windows Defender Firewall-> Advanced Settings.

Click inbound Rule in the left pane, and then click New Rule in the right pane.

On the Rule Type screen of the New inbound Rule wizard, select Port, and then click next.

On the next screen, select the type of port, then enter the port number you want to open before specific Local Port, and click next when you are finished.

On the next screen, select allow connection, and then click next.

On the profile screen, select all profiles, and then click next.

Now set a name for the rule and click finish.

You have now successfully unblocked the required ports. You can repeat the above steps to open another port, or delete this port by navigating to the "inbound" rule and deleting the corresponding rule.

This is the end of the article on "how to find out which ports are blocked by the firewall in windows". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, please share it out for more people to see.

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