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550 5.7.1 Unable to relay

    Question

  • Recently we had added new accepted domain xyz.in in our Exchange 2010 (14.2.328.10) Server and also created associated recipient policy for the same. This domain is hosted with third party and is relaying the messages after scanning to our Exchange Server.

    Now it’s seen that this relaying works perfect i.e. after sending mails from other domains like gmail, yahoo, etc. it arrives at respective user mailbox in xyz.in but suddenly stops working and sender receive message as follows:

    Hello, this is the mail server on (name of hosting server).

    I am sending you this message to inform you on the delivery status of a
    message you previously sent.  Immediately below you will find a list of
    the affected recipients; also attached is a Delivery Status Notification
    (DSN) report in standard format, as well as the headers of the original
    message.

      <test@xyz.in> delivery failed; will not continue trying

    Final-Recipient: rfc822; test@xyz.in
    Action: failed
    Status: 5.7.1 (delivery not authorized)
    Remote-MTA: dns;[NAT WAN IP of Exchange] (NAT WAN IP of Exchange)
    Diagnostic-Code: smtp;550 5.7.1 Unable to relay
    X-PowerMTA-BounceCategory: relaying-issues

    Also if Exchange Server is restarted after this issue, the relaying starts working again but same issue occurs after some time.

    Any thought on what might be causing this? 


    • Edited by Amol Kubal Monday, December 24, 2012 10:20 AM
    Monday, December 24, 2012 10:19 AM

All replies

  • Hello

    Did you tested your Exchange server connectivity from outside.

    www.testexchangeconnectivity.com

    the error seems to be unable to relay message.


    Thanks Mouzzam Hussain Visit to my Blog mouzzamh.wordpress.com

    Monday, December 24, 2012 10:41 AM
  • Yes. It gives out below message after testing :

    Testing inbound SMTP mail flow for domain test@xyz.in.

    Inbound SMTP mail flow was verified successfully.

    And in test step is shows successful connectivity details of Mail Exchanger (i.e hosting servers).

    When error is occurring at that time the message send from gmail or yahoo successfully arrives at hosting server but when hosting server relay this message to Exchange Server failure occurs and which is ultimately appears in delivery failure report. 
    • Edited by Amol Kubal Monday, December 24, 2012 11:30 AM
    Monday, December 24, 2012 11:16 AM
  • Hello

    Do you use a smart host or DNS lookup ?



    Thanks Mouzzam Hussain Visit to my Blog mouzzamh.wordpress.com

    Monday, December 24, 2012 11:27 AM
  • For outgoing messages we are using smart host.
    Monday, December 24, 2012 11:33 AM
  • May be your hosting server is unable to accept the connection from your Exchange Server did you try

    telnet port 25 to your smart host server.


    Thanks Mouzzam Hussain Visit to my Blog mouzzamh.wordpress.com

    Monday, December 24, 2012 11:39 AM
  • Ping and Telnet to port 25 of hosting server are permanently blocked. Hence can't perform this step.

    Also when had enabled protocol logging on receive connector below logs are found.

    When mail delivery is successful:

    "220 ExchangeServer.abc.com Microsoft ESMTP MAIL Service ready at Tue, 18 Dec 2012 18:49:07 +0530",

    <,EHLO Hosting Server Name,

    >,250-ExchangeServer.abc.com Hello [192.168.0.254],

    >,250-SIZE,

    >,250-PIPELINING,

    >,250-DSN,

    >,250-ENHANCEDSTATUSCODES,

    >,250-STARTTLS,

    >,250-AUTH,

    >,250-8BITMIME,

    >,250-BINARYMIME,

    >,250 CHUNKING,

    <,MAIL FROM:<test@gmail.com> BODY=8BITMIME RET=HDRS,

    2012-12-18T13:19:08.261Z,EXCHANGESERVER\Default EXCHANGESERVER,08CFAB2C94234D2E,15,192.168.0.94:25,192.168.0.254:54792,*,08CFAB2C94234D2E;2012-12-18T13:19:08.152Z;1,receiving message

    >,250 2.1.0 Sender OK,

    <,RCPT TO:<test@xyz.in>,

    >,250 2.1.5 Recipient OK,

    <,DATA,

    >,354 Start mail input; end with <CRLF>.<CRLF>,

    2012-12-18T13:19:38.573Z,EXCHANGESERVER\Default EXCHANGESERVER,08CFAB2C94234D2E,21,192.168.0.94:25,192.168.0.254:54792,*,Tarpit for '0.00:00:30.670' due to 'DelayedAck',Expired;Timeout

    >,250 2.6.0 <CAH-kzTcWt2mni5vMaH3Mi7Gp9MB_+yh0Wj0r2OOx+SqheN4_ig@mail.gmail.com> [InternalId=136347] Queued mail for delivery,

    <,QUIT,

    >,221 2.0.0 Service closing transmission channel

    When mail delivery failure occurs:

    "220 ExchangeServer.abc.com Microsoft ESMTP MAIL Service ready at Wed, 19 Dec 2012 07:47:55 +0530",

    <,EHLO Hosting Server Name,

    >,250-ExchangeServer.abc.com Hello [192.168.0.254],

    >,250-SIZE,

    >,250-PIPELINING,

    >,250-DSN,

    >,250-ENHANCEDSTATUSCODES,

    >,250-STARTTLS,

    >,250-X-ANONYMOUSTLS,

    >,250-AUTH NTLM LOGIN,

    >,250-X-EXPS GSSAPI NTLM,

    >,250-8BITMIME,

    >,250-BINARYMIME,

    >,250-CHUNKING,

    >,250-XEXCH50,

    >,250-XRDST,

    >,250 XSHADOW,

    <,MAIL FROM:<test@gmail.com> BODY=8BITMIME RET=HDRS,

    2012-12-19T02:17:56.769Z,EXCHANGESERVER\Default EXCHANGESERVER,08CFAB2C94239AE4,20,192.168.0.94:25,192.168.0.254:41641,*,08CFAB2C94239AE4;2012-12-19T02:17:56.644Z;1,receiving message

    >,250 2.1.0 Sender OK,

    <,RCPT TO:<test@xyz.in>,

    2012-12-19T02:17:56.831Z,EXCHANGESERVER\Default EXCHANGESERVER,08CFAB2C94239AE4,23,192.168.0.94:25,192.168.0.254:41641,*,Tarpit for '0.00:00:05',

    >,550 5.7.1 Unable to relay,

    <,DATA,

    2012-12-19T02:18:01.886Z,EXCHANGESERVER\Default EXCHANGESERVER,08CFAB2C94239AE4,26,192.168.0.94:25,192.168.0.254:41641,*,Tarpit for '0.00:00:05',

    >,503 5.5.2 Need rcpt command,

    <,QUIT,

    >,221 2.0.0 Service closing transmission channel

    So after comparing protocol logging, its seen that when NDR occurs 250-X-ANONYMOUSTLS, 250-AUTH NTLM LOGIN, 250-X-EXPS GSSAPI NTLM, 250-XEXCH50, 250-XRDST, 250 XSHADOW are seen instead of 250-AUTH. Now don’t know what causes it.

    Also when user failed to receive mail, he is able to send mail outside domain without any issue.



    • Edited by Amol Kubal Monday, December 24, 2012 12:05 PM
    Monday, December 24, 2012 12:04 PM
  • As I had mentioned earlier, the restarting of Exchange Server solves the problem and also if we keep the Exchange Server without restarting, after some interval relaying starts working without any intervention.

    So the main question is that, is there any service of Exchange becomes non-responsive which cause this issue and if want to check, how to proceed for the same.


    • Edited by Amol Kubal Tuesday, December 25, 2012 4:07 AM
    Tuesday, December 25, 2012 4:06 AM
  • Hello

    I would recommend you to check all the event application logs and monitor the Exchange Service,

    Run the ExBpa tool from exchange toolbox and check the report.


    Thanks Mouzzam Hussain Visit to my Blog mouzzamh.wordpress.com

    Tuesday, December 25, 2012 6:39 AM
  • Hello,

    Is there any update?


    Cara Chen
    TechNet Community Support

    Monday, December 31, 2012 9:36 AM