title: Calling simple AJAX WebMethod always results in "fail" callback
body: <p>Below code is my server side code. (C#)</p>
  
  <pre><code>            [WebMethod]
              public static string InsertCV(string edu)
              {             
                  return "";
              }
  </code></pre>
  
  <p>And Below code is my client side code. (ASP.NET)</p>
  
  <pre><code>           var edu = {"education":[{"university":"111","speciality":"222","faculty":"333","degree":"444","start":"555","end":"666"}]}
  
              var post = $.ajax(
               {
                   type: "POST",
                   data: edu,
                   url: "Add_CV.aspx/InsertCV",
                   contentType: "application/json; charset=utf-8",
                   dataType: "json",
                   async: true,
                   cache: false
               })
              post.done(function (data, teStatus, jqXHR) {
                  if (data.d == "")
                  { alert("ok"); }
              });
              post.fail(function (jqXHR, e) {
                  alert("error");
              });
  </code></pre>
  
  <p>I would like to send user's data to server with ajax post method. But everytime  <code>post.fail()</code> function executes.
  Please help me that where is my mistake.
  May be in server side <code>InsertCV(string edu)</code> , <code>string</code> is not appropriate for this situtate. I don't know.</p>