title: Strange increase in email size using SMTP class to send an email as opposed to outlook
body: <p>I am sending an email with an attachment
  using the following Code</p>
  
  <pre><code>Dim msg As New System.Net.Mail.MailMessage(req.EmailFrom, req.EmailTo)
              Dim att As New System.Net.Mail.Attachment("C:\Documents and Settings\michaelr\Desktop\1216259.pdf")
              With msg
                  .Attachments.Add(att)
                  .Body = req.EmailBody
                  .Subject = req.EmailSubject
              End With
      Dim client As New System.Net.Mail.SmtpClient()
              client.Host = PDFService(Of T).mSMTPServer
              client.Send(msg)
  </code></pre>
  
  <p>The file size of the attachment is 396KB, upon the recipient receiving the email outlook
  shows the file size as 543Kb. 
  Strange thing is if I send an email with the same attachment using outlook the file size is 
  396Kb.</p>
  
  <p>I understand that file sizes can increase due to the attachment being base 64 encoded
  as opposed to just raw binary.</p>
  
  <p>What I am failing to see is why outlook send a file which is 396KB in size but in code when
  sending it, the same file is 543Kb.</p>
  
  <p>Any help would be appreciated and get a big green tick.</p>