I send form information as a generated html attachment on an email, but when sending to clients using Lotus Notes (ver. 7.02) the attached html document is opened as part of the email body.
This does not happen in Outlook or Hotmail.
Now other, older ASP applications in the same environment send emails with HTML attachments by saving them on the server and then attaching them, so it might have something to do with the way the attachment is made with the StreamWriter, but I fail to see how that should affect the final result of the mail.
The HTML document has <!DOCTYPE html PUBLIC ""-//W3C//DTD XHTML 1.0 Transitional//EN"" ""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd
""> which I tried to change to HTML 4.0 to see if that made a difference, but it didn't.
I tried (as you will see in the code snippet) to send the body as plain text, hoping that it wouldn't attempt to blend them together, but to no avail.
Dim L_objEmailClient As New System.Net.Mail.MailMessage()
L_objEmailClient.Body = body.ToString()
L_objEmailClient.IsBodyHtml = False
Dim L_data As Byte() = Encoding.ASCII.GetBytes(attachment.ToString)
Dim L_MemoryStream As New System.IO.MemoryStream(L_data)
Dim L_StreamWriter As New System.IO.StreamWriter(L_MemoryStream)
Dim mail_Attachment As New System.Net.Mail.Attachment(L_MemoryStream, "registration.html", System.Net.Mime.MediaTypeNames.Text.Html)