C#

byte[] data = System.Text.Encoding.ASCII.GetBytes(FormVariables);

System.IO.Stream os = null;
WebRequest request = null;
WebRequest.DefaultWebProxy.Credentials = CredentialCache.DefaultCredentials;

request = WebRequest.Create(URL);

request.ContentType = "application/x-www-form-urlencoded";
request.Method = "POST";
request.ContentLength = data.Length;
request.Timeout = 420000;

os = request.GetRequestStream();
os.Write(data, 0, data.Length);
os.Close();

System.Net.WebResponse resp = null;
resp = request.GetResponse();

System.IO.StreamReader sr = new System.IO.StreamReader(resp.GetResponseStream());
strResponse = sr.ReadToEnd().Trim();

FileIOPermission f2 = new FileIOPermission(FileIOPermissionAccess.Write, "C:\\Windows\\Fonts\\");
     f2.AddPathList(FileIOPermissionAccess.Read , origin);

     try
     {
          System.IO.File.Copy(origin, destination);
     }
     catch (UnauthorizedAccessException ex)
     {
           MessageBox.Show(ex.ToString());
     }

... 
Bitmap bmp; 
... 
MemoryStream  = new MemoryStream(); 
bmp.Save(memStream, ImageFormat.Jpeg); 
... 
ContentType contentType = new ContentType(); 
contentType.MediaType = MediaTypeNames.Image.Jpeg; 
contentType.Name = "screen"; 

MailMessage mail = new MailMessage(); 
... 
mail.Attachments.Add(new Attachment(memStream, contentType)); 
... 

SmtpClient.Send(mail);