I'm currently writing some tests so that I may improve my skills with the Internet interaction through Windows Forms. One of those tests is to find a postal code which should be returned by Canada Post website. My default URL setting is set to: http://www.canadapost.ca/cpotools/apps/fpc/personal/findByCity?execution=e4s1 The required form fields are: streetNumber, streetName, city, province The contentType is "application/x-www-form-enclosed" EDIT: Please consider the value "application/x-www-form-encoded" instead of point 3 value as the contentType. (Thanks EricLaw-MSFT!) The result I get is not the result expected. I get the HTML source code of the page where I could manually enter the information to find the postal code, but not the HTML source code with the found postal code. Any idea of what I'm doing wrong? Shall I consider going the XML way? Is it first of all possible to search on Canada Post anonymously? Here's a code sample for better description: public static string FindPostalCode(ICanadadianAddress address) { var postData = string.Concat(string.Format("&streetNumber={0}", address.StreetNumber) , string.Format("&streetName={0}", address.StreetName) , string.Format("&city={0}", address.City) , string.Format("&province={0}", address.Province)); var encoding = new ASCIIEncoding(); byte[] postDataBytes = encoding.GetBytes(postData); request = (HttpWebRequest)WebRequest.Create(DefaultUrlSettings); request.ImpersonationLevel = System.Security.Principal.TokenImpersonationLevel.Anonymous; request.Container = new CookieContainer(); request.Timeout = 10000; request.ContentType = contentType; request.ContentLength = postDataBytes.LongLength; request.Method = @"post"; var senderStream = new StreamWriter(request.GetRequestStream()); senderStream.Write(postDataBytes, 0, postDataBytes.Length); senderStream.Close(); string htmlResponse = new StreamReader(request.GetResponse().GetResponseStream()).ReadToEnd(); return processedResult(htmlResponse); // Processing the HTML source code parsing, etc. } I seem stuck in a bottle neck in my point of view. I find no way out to the desired result. EDIT: There seems to have to parameters as for the ContentType of this site. Let me explain. There's one with the "meta"-variables which stipulates the following: meta http-equiv="Content-Type" content="application/xhtml+xml, text/xml, text/html; charset=utf-8" And another one later down the code that is read as: form id="fpcByAdvancedSearch:fpcSearch" name="fpcByAdvancedSearch:fpcSearch" method="post" action="/cpotools/apps/fpc/personal/findByCity?execution=e1s1" enctype="application/x-www-form-urlencoded" My question is the following: With which one do I have to stick? Let me guess, the first ContentType is to be considered as the second is only for another request to a function or so when the data is posted? EDIT: As per request, the closer to the solution I am is listed under this question: WebRequest: How to find a postal code using a WebRequest against this ContentType=”application/xhtml+xml, text/xml, text/html; charset=utf-8”? Thanks for any help! :-)