get parameters in mvc 4 when send parameter of webrequest in windows application

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C#

hi , please answer my question .
i have send parameters into mvc 4 project of windows application with webrequest .
i do work with under code
code in windows application :

public string GetInformation(string strGUID)
        {
              
                string str = string.Format("{0}@{1}", strGUID, "GetInfor");
                string str2 = HttpPost("http://www.mysite.com/Customers/GetCustomerInformations", str);
                if (str2 != "")
                {
                    string[] strResult = str2.Split('@');
                }
               
                return str2;
            }

        public static string HttpPost(string URI, string Parameters)
        {
            string strResult = "";
            try
            {
                System.Net.WebRequest req = System.Net.WebRequest.Create(URI);
                req.ContentType = "application/x-www-form-urlencoded";
                req.Method = "POST";
                byte[] bytes = System.Text.Encoding.UTF8.GetBytes(Parameters);
                req.ContentLength = bytes.Length;
                System.IO.Stream os = req.GetRequestStream();
                os.Write(bytes, 0, bytes.Length);
                os.Close();
                System.Net.WebResponse resp = req.GetResponse();
                if (resp == null) return null;
                StreamReader sr = new StreamReader(resp.GetResponseStream());
                strResult = sr.ReadToEnd().Trim();
            }
            catch (Exception e)
            {
                strResult = "";
               
            }
            return strResult;
        }

the code in mvc 4:

[HttpPost]
       public ActionResult GetCustomerInformations()
       {
           string SendInformation = string.Format("{0}@{1}", "D", "3000");
           try
           {
               Request.InputStream.Position = 0;
               if ( HttpContext.Request.InputStream != null)
               {
                   StreamReader reader = new StreamReader(HttpContext.Request.InputStream);
                   String xmlData = reader.ReadToEnd();
                   string[] strrequest = xmlData.Split('@');
                   var findCustomer = Customer.GetByGUID(strrequest[0]);
                   if (findCustomer != null)
                   {

                       SendInformation = string.Format("{0}@{1}@{2}@{3}@{4}@{5}@{6}@{7}@{8}@{9}@{10}", findCustomer.Company, findCustomer.Tel, findCustomer.Tel2,
                        findCustomer.Fax, findCustomer.Email, findCustomer.Name, findCustomer.Version, findCustomer.InstallOnDate, findCustomer.InstallOnDateM,
                        findCustomer.InstallPath, findCustomer.Address);
                   }
                   else
                   {
                       SendInformation = string.Format("{0}@{1}", "D", "3001-notfindCustomers" + "-Code:" + strrequest[0] );
                   }

               }
               else
               {
                   SendInformation = string.Format("{0}@{1}", "D", "3010-nullString");//new
               }
           }
           catch
           {
               SendInformation = string.Format("{0}@{1}", "D", "2001-cash");
           };
           return Content(SendInformation);
       }

this code is worked with .net framework 4 , but when update host to .net framework 4.5 this code not worked , when call action in mvc 4 get error 404 page not found and when remove [httpPost] not send parameters in windows application , and Request.InputStream is empty

please help me . please say me how to resolved this .