Can't Listen to Port 80 on Windows 7

Question

I am attempting to create a socket listener in a Windows application using a System.Net.Sockets.Socket but I could not bind to port 80 on my Windows 7 machine, I could bind to any other port without issue but attempting to bind to 80 always resulted in:

an attempt was made to access a socket in a way forbidden by its access permissions

I discovered that IIS running locally locked up port 80 and that I had to move IIS to another port - you can read how to d os by going to http://www.ultimateproxylist.com/ChangingIIS.aspx
The problem I still have - even after moving IIS off of Port 80 - is that no listener is actually working. I even grabbed the following code sample directly off the MSDN site and even IT does not work! I am on a Windows 7 machine - any ideas?!?

 
if (!HttpListener.IsSupported)
{
Console.WriteLine("Windows XP SP2 or Server 2003 is required to use the HttpListener class.");
return;
}

// Create a listener.
HttpListener listener = new HttpListener();

// Add the prefixes.
listener.Prefixes.Add("http://*:80/");
listener.Start();
Console.WriteLine("Listening...");
// Note: The GetContext method blocks while waiting for a request. 
HttpListenerContext context = listener.GetContext();
HttpListenerRequest request = context.Request;
// Obtain a response object.
HttpListenerResponse response = context.Response;
// Construct a response.
string responseString = "<HTML><BODY> Hello world!</BODY></HTML>";
byte[] buffer = System.Text.Encoding.UTF8.GetBytes(responseString);
// Get a response stream and write the response to it.
response.ContentLength64 = buffer.Length;
System.IO.Stream output = response.OutputStream;
output.Write(buffer, 0, buffer.Length);
// You must close the output stream.
output.Close();
listener.Stop();

Sam Hobbs · Answer

That explains things. Then you need a packet sniffer. I doubt that you can do much of that using .Net but look at the following articles. One of them uses WinPcap  which is very highly used. Simple Sniffer in C# Packet Sniffer in C#

Ken Tola · Answer

I am actually trying to listen to traffic on port 80 specifically to view browser traffic. The issue I think is that all of the listeners assume traffic is being directed to them and not somewhere else. It is relatively easy for example to write a TCP Server in one console app and a TCP Client in another console app and then have the Client submit data via a TCP address and port to the Server. There are tons of samples on that and I was writing chat programs 7 years ago that had that functionality. The issue here is how to listen to traffic as it goes from a browser through a local IP connection and out to the world. None of the listeners or socket classes seem to be able to accomplish this task...

Sam Hobbs · Answer

How do you know that the problem is unique to Windows 7? Does the code work on other systems? Do you know what port 80 is used for? I am not sure I understand what you are trying to do but it makes sense to me that you can't do it. Do you have any browser (such as IE) windows open when you do that? If you can use some other port while testing then that will probably work better. You can change to port 80 after testing but my guess is that even then port 80 will be a problem.