Windows Vista Forums

The connection was dropped due to an SMTP protocol event sink.
  1. #1


    JJ Guest

    The connection was dropped due to an SMTP protocol event sink.

    Hello,
    Today noticed large email queue on SBS2003, cannot send emails to any
    outside domain, and in addiditional queue information i see this message -
    The connection was dropped due to an SMTP protocol event sink.
    Our SBS2003 is used for email recieving and sending, no external smart
    hosts and server is behind firewall. Looks like our internal AD DNS is
    working fine, i can recieve recrusive answers from DNS(cheked with nslookup),
    also i can connect with telnet to port 25 to any mail server in queue, also i
    can connect to my server from interet with telnet on port 25. I enabled
    diagnostic logging for ms exchange transport and in event log saw these
    messages: "Message delivery to the host xxx.xxx.xx.xx failed while delivering
    to the remote domain 'domain.eu' for the following reason: The connection
    was dropped due to an SMTP protocol event sink.
    The SMTP verb which caused the error is 'quit'. The response from the
    remote server is ''.
    Of course i restarted server few times, but no changes, also cheked our
    MX and PTR records at ISP DNS, and our external ip isn't listed in any rbl.
    Uninstalled antivirus software from server, because some people had similar
    problems from antivirus.






      My System SpecsSystem Spec

  2. #2


    Larry Struckmeyer[SBS-MVP] Guest

    Re: The connection was dropped due to an SMTP protocol event sink.

    Hi JJ:

    that message is not definitive, unfortuntly. Besides this, what errors related
    to exchange or smtp are in the event logs?

    Are there only messages orginating on your network in the outbound queue,
    or are there hundreds/thousands that orginated somewhere else?

    Have you turned up logging on the exchage in Echange Server Manager?

    Please post the results of the command: ipconfig /all > c:\iptest.txt.
    -
    Larry
    Please post the resolution to your
    issue so others may benefit
    -
    Get Your SBS Health Check at
    www.sbsbpa.com


    > Hello,
    > Today noticed large email queue on SBS2003, cannot send emails to
    > any
    > outside domain, and in addiditional queue information i see this
    > message -
    > The connection was dropped due to an SMTP protocol event sink.
    > Our SBS2003 is used for email recieving and sending, no external
    > smart
    > hosts and server is behind firewall. Looks like our internal AD DNS is
    > working fine, i can recieve recrusive answers from DNS(cheked with
    > nslookup),
    > also i can connect with telnet to port 25 to any mail server in queue,
    > also i
    > can connect to my server from interet with telnet on port 25. I
    > enabled
    > diagnostic logging for ms exchange transport and in event log saw
    > these
    > messages: "Message delivery to the host xxx.xxx.xx.xx failed while
    > delivering
    > to the remote domain 'domain.eu' for the following reason: The
    > connection
    > was dropped due to an SMTP protocol event sink.
    > The SMTP verb which caused the error is 'quit'. The response from
    > the
    > remote server is ''.
    > Of course i restarted server few times, but no changes, also cheked
    > our
    > MX and PTR records at ISP DNS, and our external ip isn't listed in any
    > rbl.
    > Uninstalled antivirus software from server, because some people had
    > similar problems from antivirus.
    >


      My System SpecsSystem Spec

  3. #3


    Ace Fekay [MCT] Guest

    Re: The connection was dropped due to an SMTP protocol event sink.

    "JJ" <JJ@newsgroup> wrote in message
    news:369CC53B-2C1F-462A-8372-B4B33D43E072@newsgroup

    > Hello,
    > Today noticed large email queue on SBS2003, cannot send emails to any
    > outside domain, and in addiditional queue information i see this message -
    > The connection was dropped due to an SMTP protocol event sink.
    > Our SBS2003 is used for email recieving and sending, no external smart
    > hosts and server is behind firewall. Looks like our internal AD DNS is
    > working fine, i can recieve recrusive answers from DNS(cheked with
    > nslookup),
    > also i can connect with telnet to port 25 to any mail server in queue,
    > also i
    > can connect to my server from interet with telnet on port 25. I enabled
    > diagnostic logging for ms exchange transport and in event log saw these
    > messages: "Message delivery to the host xxx.xxx.xx.xx failed while
    > delivering
    > to the remote domain 'domain.eu' for the following reason: The connection
    > was dropped due to an SMTP protocol event sink.
    > The SMTP verb which caused the error is 'quit'. The response from the
    > remote server is ''.
    > Of course i restarted server few times, but no changes, also cheked our
    > MX and PTR records at ISP DNS, and our external ip isn't listed in any
    > rbl.
    > Uninstalled antivirus software from server, because some people had
    > similar
    > problems from antivirus.
    >
    >
    >

    The Event sink portion seems to be indicating a third party Exchange app is
    installed. It could be an antivirus, XClaimer, etc. What is installed on the
    machine?

    Are you getting EventID 2012 or 2013 errors?

    Is this happening with normal domains that you send to, or ones you do not
    recognize? You could be under an attack someone trying to relay through your
    server.

    One thing I did find when I searched on this error, is the following quote
    from Exchange-experts.com.
    http://www.experts-exchange.com/Netw..._21110083.html

    He didn't indicate it, but my guess his issue may have been that the
    Exchange folders were not excluded from the antivirus scanning.

    "i fixed this. disabling the anti-virus, re-installing smtp, then
    re-installing exchange. bout 12 hours now. wanted to thank everyone for
    their help with this so i split the points. "


    --
    Ace

    This posting is provided "AS-IS" with no warranties or guarantees and
    confers no rights.

    Please reply back to the newsgroup or forum for collaboration benefit among
    responding engineers, and to help others benefit from your resolution.

    Ace Fekay, MCT, MCITP EA, MCTS Windows 2008 & Exchange 2007, MCSE & MCSA
    2003/2000, MCSA Messaging 2003
    Microsoft Certified Trainer

    For urgent issues, please contact Microsoft PSS directly. Please check
    http://support.microsoft.com for regional support phone numbers.



      My System SpecsSystem Spec

  4. #4


    JJ Guest

    Re: The connection was dropped due to an SMTP protocol event sink.

    Hello,
    I found where was problem, we have Astaro firewall(hardware appliance), this
    box have smtp proxy, antispam and antivirus functions, like greylisting,
    batv, spf chek, rbl chek and so on, found that one engine just hangs up(even
    without error message) for outgoing emails, disabled it and everything
    started to work. I will contact Astaro support for more information, but
    looks like everything is ok with Exchange. Yes, i believe in some situations
    it could be caused by installed antivirus, if it have some antispam or
    firewall functions, but not in this case.


    Thanks,
    JJ.

    "Ace Fekay [MCT]" wrote:

    > "JJ" <JJ@newsgroup> wrote in message
    > news:369CC53B-2C1F-462A-8372-B4B33D43E072@newsgroup

    > > Hello,
    > > Today noticed large email queue on SBS2003, cannot send emails to any
    > > outside domain, and in addiditional queue information i see this message -
    > > The connection was dropped due to an SMTP protocol event sink.
    > > Our SBS2003 is used for email recieving and sending, no external smart
    > > hosts and server is behind firewall. Looks like our internal AD DNS is
    > > working fine, i can recieve recrusive answers from DNS(cheked with
    > > nslookup),
    > > also i can connect with telnet to port 25 to any mail server in queue,
    > > also i
    > > can connect to my server from interet with telnet on port 25. I enabled
    > > diagnostic logging for ms exchange transport and in event log saw these
    > > messages: "Message delivery to the host xxx.xxx.xx.xx failed while
    > > delivering
    > > to the remote domain 'domain.eu' for the following reason: The connection
    > > was dropped due to an SMTP protocol event sink.
    > > The SMTP verb which caused the error is 'quit'. The response from the
    > > remote server is ''.
    > > Of course i restarted server few times, but no changes, also cheked our
    > > MX and PTR records at ISP DNS, and our external ip isn't listed in any
    > > rbl.
    > > Uninstalled antivirus software from server, because some people had
    > > similar
    > > problems from antivirus.
    > >
    > >
    > >
    >
    >
    > The Event sink portion seems to be indicating a third party Exchange app is
    > installed. It could be an antivirus, XClaimer, etc. What is installed on the
    > machine?
    >
    > Are you getting EventID 2012 or 2013 errors?
    >
    > Is this happening with normal domains that you send to, or ones you do not
    > recognize? You could be under an attack someone trying to relay through your
    > server.
    >
    > One thing I did find when I searched on this error, is the following quote
    > from Exchange-experts.com.
    > http://www.experts-exchange.com/Netw..._21110083.html
    >
    > He didn't indicate it, but my guess his issue may have been that the
    > Exchange folders were not excluded from the antivirus scanning.
    >
    > "i fixed this. disabling the anti-virus, re-installing smtp, then
    > re-installing exchange. bout 12 hours now. wanted to thank everyone for
    > their help with this so i split the points. "
    >
    >
    > --
    > Ace
    >
    > This posting is provided "AS-IS" with no warranties or guarantees and
    > confers no rights.
    >
    > Please reply back to the newsgroup or forum for collaboration benefit among
    > responding engineers, and to help others benefit from your resolution.
    >
    > Ace Fekay, MCT, MCITP EA, MCTS Windows 2008 & Exchange 2007, MCSE & MCSA
    > 2003/2000, MCSA Messaging 2003
    > Microsoft Certified Trainer
    >
    > For urgent issues, please contact Microsoft PSS directly. Please check
    > http://support.microsoft.com for regional support phone numbers.
    >
    >
    > .
    >

      My System SpecsSystem Spec

  5. #5


    Ace Fekay [MCT] Guest

    Re: The connection was dropped due to an SMTP protocol event sink.

    "JJ" <JJ@newsgroup> wrote in message
    news:CE677018-623B-4501-83AA-8EFEAD9A8D98@newsgroup

    > Hello,
    > I found where was problem, we have Astaro firewall(hardware appliance),
    > this
    > box have smtp proxy, antispam and antivirus functions, like greylisting,
    > batv, spf chek, rbl chek and so on, found that one engine just hangs
    > up(even
    > without error message) for outgoing emails, disabled it and everything
    > started to work. I will contact Astaro support for more information, but
    > looks like everything is ok with Exchange. Yes, i believe in some
    > situations
    > it could be caused by installed antivirus, if it have some antispam or
    > firewall functions, but not in this case.
    >
    >
    > Thanks,
    > JJ.
    Good to hear you pinpointed the problem. Let us know what their tech support
    says.

    Ace



      My System SpecsSystem Spec

The connection was dropped due to an SMTP protocol event sink. problems?

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