Error When Downloading a File from secured Share Point Server from MVC 4 Application

I am developing MVC 4 Razor Application.

I  Placed  a “ Action Link “ Download Button which downloads file from HTTPS Sharepoint Server.

Error : Am getting 403 Forbidden Error in Web Request

Code Snippet :

string url = "https://xyz.com/files/sample.docx"; --à SharePoint Server File URL

            WebRequest request = WebRequest.Create(new Uri(url, UriKind.Absolute));

            request.Credentials = new NetworkCredential("XYZ", "XYZ");

            WebResponse response = request.GetResponse();

            Stream fs = response.GetResponseStream() as Stream;

            byte[] buffer = new byte[16 * 1024];

            using (MemoryStream ms = new MemoryStream()) {

                fs.CopyTo(ms);

              buffer=  ms.ToArray();

            }

            return File(buffer, "application/vnd.openxmlformats-officedocument.wordprocessingml.document", fileName);

I got 403 Forbidden Exception in Highlighted Area.