#17 Email not send if attachment used

[Rick Morayniss]

My issue at the moment,is if an attachment is being used, the email does not get send, and there is no error message. The file name is correct, I have verified that. Whith this code I get no email, but no error message as well.
Here is an example
string strdtfile = DateTime.Now.ToString("yyyyMMddHHmmss");
string FilePath = @Server.MapPath("~/Temp/" + strdtfile + ".pdf");
currentReport.ExportToPdf(FilePath);
var mymessage = new MimeMailMessage();
mymessage.From = new MimeMailAddress(Mail);
mymessage.Subject = "Web Purchase Receipt " + DateTime.Now.ToString("yyyyMMdd");
mymessage.To.Add(Session["email"].ToString());
mymessage.Body = "";
mymessage.IsBodyHtml = true;
mymessage.To.Add(Session["email"].ToString());
var mailer = new MimeMailer(Host, 465)
{
User = User,
Password = Pass,
EnableImplicitSsl = true,
AuthenticationMode = AuthenticationType.Base64
};

        mymessage.Attachments.Add(new MimeAttachment(FilePath));

        ((SmtpSocketClient)mailer).SslType = SslMode.Ssl;

        mailer.SendCompleted += SendCompleted;
        mailer.SendMailAsync(mymessage);

[Dmitry N]

Had the same issue, mail server reported: "554 Too long line was received" when I tried to add an attachment.

Fixed it by adding "\r\n" to stream chunks in SmtpSocketClient.cs, at the end of SendAttachments() method:

...

          char[] bufln = new char[2] { '\r', '\n' };

            while (num > 0)
            {                   
                _con.SendData(Encoding.ASCII.GetChars(fbuf, 0, num), 0, num);
                _con.SendData(bufln, 0, 2);   // <--------
                num = cs.Read(fbuf, 0, 2048);
            }
        ...

[Araz Farhang Dareshuri]

May I ask if you have any explenation for this?

[Dmitry N]

Attachment is sent as a base64-encoded string and it looks like some email servers (hMailServer in my case) have limits for string length . So basically I just split one huge line to smaller parts.

[Araz Farhang Dareshuri]

Great, would you be kind enough to do a pull request?