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Unknown e-mails in client inbox

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  • Unknown e-mails in client inbox

    Our office is running exchange 2003

    One of the Clients noticed that she is recieving a lot of "System administrator Undelivarable mails with subjects as " buy gem stones at Gemstore " all these e-mails ar not familiar for her
    I did a quick look at the exchange Queues and i see a lot of unknown hostnames trying to send Outbound mails from our server.

    I do not know how come they are in our system but i know i want them out .. are there options to freeze and disable them ,

    How can i trace back if these are the undeliverable mails my client is having ?

    But how can i keep them out

    Please help me out ..appreciate

  • #2
    Re: Unknown e-mails in client inbox

    Make sure you have followed this

    Please read this before you post:

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    • #3
      Re: Unknown e-mails in client inbox

      You don't see hostnames in the Queue viewer, you see remote email domains. Can you clarify what you are seeing. Are you saying that you see a lot of remote email domains with email queued up for delivery to them?


      • #4
        Re: Unknown e-mails in client inbox

        Sounds like backscatter of spoofing to me.
        Systems Administrator emails are NDRs.
        The spammer has send their emails with your user as the From address. Clueless network admins are accepting the messages then attempting to send them back to the "sender" because they are spam. As your user is the "sender" they get the NDR.

        Unfortunately you cannot block the delivery of the NDR. If you do then your server will get blacklisted. The RFCs, which control how SMTP works, state that the receiving server must accept the NDRs that are destined for it. If you want to block/drop them after they have been delivered then you can - a good antispam application should be able to do that for you - Exchange cannot on its own.

        Simon Butler
        Exchange MVP

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