WCF Service Connection Refused: How to Troubleshoot 'No connection could be made because the target machine actively refused it 127.0.0.1:3446'?

WCF service error: "Unable to establish connection..." Troubleshooting Guide

When trying to upload a file via a WCF stream and encountering the error message "The connection could not be established because the target machine actively rejected it 127.0.0.1:3446", it is important to determine the root cause.

Possible causes and solutions:

An "Active Rejection" error indicates that the connection attempt was rejected by the host. This may be due to a firewall blocking the connection or the service host not listening on the specified port (3446).

1. Check your firewall settings: Make sure your firewall is not blocking connections to the service. Consider temporarily disabling the firewall for testing.

2. Verify service host status: Confirm that the service hosting the WCF implementation is running and listening on the correct port. Execute the following command in the command prompt:

   <code> netstat -anb</code>

   (For Linux systems, change to "netstat -anp")

   Verify that the service is listed and listening on the expected port.

3. Local testing: Create a simple test application to connect to the service locally. This will help isolate any network issues. For example:

   <code class="language-c#"> byte[] fileStream;
    using (FileStream fs = new FileStream("E:\stream.txt", FileMode.Open, FileAccess.Read, FileShare.Read))
    {
        fileStream = new byte[fs.Length];
        fs.Read(fileStream, 0, (int)fs.Length);
    }
   
    string baseAddress = "http://localhost:3446/File/AddStream/stream.txt";
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(baseAddress);
    request.Method = "POST";
    request.ContentType = "text/plain";
   
    Stream serverStream = request.GetRequestStream();
    serverStream.Write(fileStream, 0, fileStream.Length);</code>

If the local test is successful, the problem may lie with the external network connection or server configuration.

The above is the detailed content of WCF Service Connection Refused: How to Troubleshoot 'No connection could be made because the target machine actively refused it 127.0.0.1:3446'?. For more information, please follow other related articles on the PHP Chinese website!