SMTP Issue - Rebex.Net.SmtpException: The server has closed the connection

0 votes
asked Jul 18, 2016 by satarupa2511 (170 points)

HI, We are using Rebex version 1.0 and use this for sending web email using SMTP.net.dll. However while sending multiple emails, we see below issue - Rebex.Net.SmtpException: The server has closed the connection. PLEASE NOTE : This issue is not consistently reproducible.

Attached is the log for more details -

2016-07-18 14:29:26.138 Opening log file.
2016-07-18 14:29:33.462 Opening log file.
2016-07-18 14:29:33.467 INFO Smtp(2) Command: MAIL FROM:ttintuit@yahoo.com SIZE=59590
2016-07-18 14:29:33.891 INFO Smtp(2) Response: 250 OK , completed
2016-07-18 14:29:33.891 INFO Smtp(2) Command: RCPT TO:c2@blank.com
2016-07-18 14:29:34.316 INFO Smtp(2) Response: 250 OK , completed
2016-07-18 14:29:34.316 INFO Smtp(2) Command: DATA
2016-07-18 14:29:34.742 INFO Smtp(2) Response: 354 Start Mail. End with CRLF.CRLF
2016-07-18 14:29:36.944 INFO Smtp(2) Response: 250 OK , completed
2016-07-18 14:40:36.444 INFO Smtp(2) Command: MAIL FROM:ttintuit@yahoo.com SIZE=58718
2016-07-18 14:40:36.448 DEBUG Smtp(2) Info: Connection closed.
2016-07-18 14:40:36.450 ERROR Smtp(2) Info: Rebex.Net.SmtpException: The server has closed the connection.
at wWGvS.bWfGzD.BMJzdYZ()
at wWGvS.bWfGzD.BbLKfs(String& )
at wWGvS.bWfGzD.KsZclZ()
at Rebex.Net.Smtp.cgrDQE(Int32 , Boolean )
at Rebex.Net.Smtp.COvOkZ(String , String )
at Rebex.Net.Smtp.bUTESW(String , String[] , String , Stream )
at Rebex.Net.Smtp.BTPxIKZ(MimeMessage , Stream , MailAddress , MailAddressCollection )
at Rebex.Net.Smtp.Send(MailMessage mail, String sender, String recipients)
2016-07-18 14:41:32.182 INFO Smtp(3) Info: Connecting to smtp.mail.yahoo.com:465 using Smtp 1.0.3854.0.
2016-07-18 14:41:32.693 DEBUG Smtp(3) Info: Connection succeeded.
2016-07-18 14:41:32.693 DEBUG Smtp(3) Info: Upgrading connection to TLS/SSL.
2016-07-18 14:41:32.695 INFO Smtp(3) TLS: State StateChange:Negotiating
2016-07-18 14:41:32.695 DEBUG Smtp(3) TLS: HandshakeMessage:ClientHello was sent.
2016-07-18 14:41:32.943 DEBUG Smtp(3) TLS: HandshakeMessage:ServerHello was received.
2016-07-18 14:41:32.943 DEBUG Smtp(3) TLS: HandshakeMessage:Certificate was received.
2016-07-18 14:41:32.943 DEBUG Smtp(3) TLS: HandshakeMessage:ServerHelloDone was received.
2016-07-18 14:41:32.943 DEBUG Smtp(3) TLS: Verifying server certificate ('C=US, S=California, L=Sunnyvale, O=Yahoo Inc., OU=Information Technology, CN=smtp.mail.yahoo.com').
2016-07-18 14:41:32.944 DEBUG Smtp(3) TLS: Certificate verification result: Accept
2016-07-18 14:41:32.953 DEBUG Smtp(3) TLS: HandshakeMessage:ClientKeyExchange was sent.
2016-07-18 14:41:32.970 DEBUG Smtp(3) TLS: CipherSpec:ChangeCipherSpec was sent.
2016-07-18 14:41:32.970 DEBUG Smtp(3) TLS: HandshakeMessage:Finished was sent.
2016-07-18 14:41:33.220 DEBUG Smtp(3) TLS: CipherSpec:ChangeCipherSpec was received.
2016-07-18 14:41:33.220 DEBUG Smtp(3) TLS: HandshakeMessage:Finished was received.
2016-07-18 14:41:33.220 INFO Smtp(3) TLS: State StateChange:Secured
2016-07-18 14:41:33.221 INFO Smtp(3) TLS: Connection secured using cipher: TLS 1.0, RSA, 128bit AES in CBC mode, SHA1
2016-07-18 14:41:33.222 DEBUG Smtp(3) TLS: Session ID:
8D-37-8F-5B-A1-22-8F-6C-71-8A-83-0C-1C-0D-F6-63-78-CF-AB-26-04-6B-D6-48
B2-B7-60-EE-6C-27-8F-71
2016-07-18 14:41:33.222 DEBUG Smtp(3) Info: Connection upgraded to TLS/SSL.
2016-07-18 14:41:33.669 INFO Smtp(3) Response: 220 smtp.mail.yahoo.com ESMTP ready
2016-07-18 14:41:33.669 INFO Smtp(3) Command: EHLO banvmkumar24
2016-07-18 14:41:33.915 INFO Smtp(3) Response: 250-smtp.mail.yahoo.com
2016-07-18 14:41:33.915 INFO Smtp(3) Response: 250-PIPELINING
2016-07-18 14:41:33.915 INFO Smtp(3) Response: 250-SIZE 41697280
2016-07-18 14:41:33.915 INFO Smtp(3) Response: 250-8 BITMIME
2016-07-18 14:41:33.915 INFO Smtp(3) Response: 250 AUTH PLAIN LOGIN XOAUTH2 XYMCOOKIE
2016-07-18 14:41:33.916 INFO Smtp(3) Command: AUTH PLAIN ****************************************
2016-07-18 14:41:35.494 INFO Smtp(3) Response: 235 2.0.0 OK
2016-07-18 14:41:35.494 INFO Smtp(3) Command: NOOP
2016-07-18 14:41:35.995 INFO Smtp(3) Response: 250 OK , completed
2016-07-18 14:41:36.000 INFO Smtp(3) Command: MAIL FROM:ttintuit@yahoo.com SIZE=58238
2016-07-18 14:41:36.501 INFO Smtp(3) Response: 250 OK , completed
2016-07-18 14:41:36.501 INFO Smtp(3) Command: RCPT TO:x@dummy.com
2016-07-18 14:41:37.001 INFO Smtp(3) Response: 250 OK , completed
2016-07-18 14:41:37.001 INFO Smtp(3) Command: DATA
2016-07-18 14:41:37.502 INFO Smtp(3) Response: 354 Start Mail. End with CRLF.CRLF
2016-07-18 14:41:39.637 INFO Smtp(3) Response: 250 OK , completed
2016-07-18 14:41:39.659 INFO Smtp(3) Command: MAIL FROM:ttintuit@yahoo.com SIZE=58238
2016-07-18 14:41:40.159 INFO Smtp(3) Response: 250 OK , completed
2016-07-18 14:41:40.160 INFO Smtp(3) Command: RCPT TO:x@dummy.com
2016-07-18 14:41:40.660 INFO Smtp(3) Response: 250 OK , completed
2016-07-18 14:41:40.660 INFO Smtp(3) Command: DATA

Applies to: Rebex Secure Mail

1 Answer

0 votes
answered Jul 18, 2016 by Lukas Matyska (55,430 points)

Hello, you are using version released before 6 years. It is possible that the problem is already solved. Can you please try the current version.

commented Jul 18, 2016 by satarupa2511 (170 points)
Thank you Lukas, I will try that. Please answer the other query posted regarding security standards.
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