Fiddler not sniffing soap traffic from asp net website


ASP.NET is a popular programming language used for building dynamic web applications. It provides a framework for developing web pages and web services, making it easier to create and maintain robust and scalable web applications. However, like any programming language, ASP.NET can sometimes present challenges that need to be addressed.

The Problem

One common issue that developers may encounter is when Fiddler, a web debugging proxy, fails to sniff SOAP traffic from an ASP.NET website. SOAP (Simple Object Access Protocol) is a protocol used for exchanging structured information in web services.

Possible Causes

There can be several reasons why Fiddler may not be able to capture SOAP traffic from an ASP.NET website. Some possible causes include:

  • Incorrect Fiddler configuration
  • Missing or misconfigured HTTP headers
  • Firewall or security blocking Fiddler
  • Issues with the ASP.NET application


To the problem of Fiddler not sniffing SOAP traffic from an ASP.NET website, you can follow these steps:

Step 1: Verify Fiddler Configuration

First, ensure that Fiddler is properly configured to capture web traffic. that the “Capture Traffic” option is enabled in Fiddler's settings. Additionally, make sure that Fiddler's proxy settings are correctly configured in your web browser.

Step 2: Check HTTP Headers

Inspect the HTTP headers of the SOAP requests and responses to ensure they are correctly formatted. Fiddler relies on these headers to capture and display the traffic. Look for any missing or misconfigured headers that may be causing the issue.

Step 3: Disable Firewalls or Security Settings

If you have a firewall or security software installed on your , it may be blocking Fiddler from the SOAP traffic. Temporarily disable any firewalls or security settings and check if Fiddler is now able to sniff the traffic.

Step 4: Debug the ASP.NET Application

If the above steps do not the issue, it's possible that there is an issue with the ASP.NET application itself. Debug the application to identify any potential errors or misconfigurations that may be Fiddler from capturing the SOAP traffic.


Here is an example of how you can use Fiddler to capture SOAP traffic from an ASP.NET website:

// Code snippet to make a SOAP request using ASP.NET

using System;
using System.Net;
using System.IO;

public class SoapClient
    public string MakeSoapRequest(string url, string soapEnvelope)
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
        request.Method = "POST";
        request.ContentType = "text/xml";
        using (StreamWriter writer = new StreamWriter(request.GetRequestStream()))
        using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
            using (StreamReader reader = new StreamReader(response.GetResponseStream()))
                return reader.ReadToEnd();

// Usage example
string url = "";
string soapEnvelope = "London";

SoapClient client = new SoapClient();
string response = client.MakeSoapRequest(url, soapEnvelope);


In this example, we create a simple SOAP client in ASP.NET that makes a SOAP request to a specified URL. The SOAP envelope is constructed as a string and sent as the request body. The response is then read and returned as a string.


By following the steps outlined above and ensuring proper configuration and debugging, you be able to solve the issue of Fiddler not sniffing SOAP traffic from an ASP.NET website. Remember to check Fiddler's settings, inspect HTTP headers, disable firewalls if necessary, and debug the ASP.NET application to identify any potential issues. With these solutions, you can effectively troubleshoot and resolve the problem, allowing you to capture and analyze SOAP traffic with Fiddler.

Rate this post

Leave a Reply

Your email address will not be published. Required fields are marked *

Table of Contents