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Email send errors

Discussion in 'E-mail Discussions' started by HyperThink, Oct 23, 2007.

  1. HyperThink

    HyperThink Registered

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    I'm new to the thread and hoping to get some help.

    The error that is being reported from the sender to my customer email is this: (I had to type this because they sent a fax of the error. i also did not include exact info for privacy reasons)

    550 Callback setup failed while verifying joeshmo@domain.com
    550 Called: 70.XX.X.XXX
    550 Sent: MAIL FROM
    550 Response: 550 5.7.1 Access denied. IP name lookup failed[75.xx.xxx.xx] SRC003 Contact postmaster@****.net
    550 The initial connection, or HELO or MAIL FROM command was rejected Refusing MAIL FROM does not help fight spam, disregards RFC requirements and stops you from receiving standard bounce meddages. This host does not accespt mail from domains whose servers refuse bounces
    550 Sender verify failed


    Then it gives :
    503 All RCPT commands were rejected with this error
    503 Sender verify failed
    503 Valide RCPT command must precede DATA

    It should be noted that there is no spam filtering on this domain.

    Can anyone help me with this?

    Thanks
     
    #1 HyperThink, Oct 23, 2007
    Last edited: Oct 23, 2007
  2. mtindor

    mtindor Well-Known Member

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    Hmm, I'm not sure I understand whether you operate the sending mail server or the receiving mail server.

    Are you using Cpanel? Are you saying that a customer of yours (on your cpanel server) is attempting to send mail to a remote email address (one not on your server) and that the remote server is sending that error back to you?

    That's a typical Exchange / SBS 2003 error message. So it seems to me that either you are here seeking help for an MS Exchange issue, or that your customer (on your Cpanel server) is the sender and is getting that message back from the recipient mail server.

    Can you elaborate?

    The receiving mail system (the one that generated that error) - and it is an Exchange server. It is saying that the sender mail server does not have an rDNS record. It may also be saying that the sender mail server is refusing to accept NDRs.

    The operator of the sender mail server should make sure that they have appropriate reverse DNS in place for IP 75.xx.xxx.xx. The operator of the sender mail server should also make sure they have not configured their mail system to reject/refuse bounces.

    Mike


     
  3. HyperThink

    HyperThink Registered

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    I am using cpanel/whm on apache.

    The problem is my customer is not getting emails. The error message is from one of their customers. It is a sporatic problem. We just changed IP address which might have something to do with it.

    Need more info?
     
  4. mtindor

    mtindor Well-Known Member

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    Yeah, but I probably need more info than what you want to post publicly. I'd really prefer to kknow the exact sender email address, recipient email address, and the ip address of any mail servers involved.

    So somebody (not on your cpanel server) is sending emails to your customer (who is on your cpanel server) and supposedly your cpanel server is sending back that rejection? I don't buy that. It could be an issue where dns changes for the new ip address haven't propogated and the mail server of the sender is trying to send to the old IP address.

    But yeah, more information would be needed. Ideally you need to have the sender send you a copy of the original email send to your customer (with full message headers intact) as well as a copy of the full reject message they received (with the ability to view its full message headers too) in order to figure out what is going on.

    Mike
     
  5. HyperThink

    HyperThink Registered

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    What don't you buy? The fact that the email to my customer using cpanel is being rejected?

    The IP switch happened almost two weeks ago. I thought it would have propogated already.

    I did look at a couple of the emails being sent and none of them have attachments which sometimes cause bounce backs.

    Sorry for not providing more specs I just am a little leery of giving out certain info.
     
  6. HyperThink

    HyperThink Registered

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    Fixed

    Here was the fix for anyone who reads this:

    Go to Exim Configuration Editor in WHM.

    Find:** Use callouts to verify the existence of email senders. Basiclly, exim will connect to the mail exchanger for a given address to make sure it exists before accepting mail from it.

    Uncheck the box and save.

    Hope this helps anyone in the future.
     
  7. mtindor

    mtindor Well-Known Member

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    I guess disabling that should have been the first thing I thought off based upon the first few lines of the error you posted. However, I was still unsure who was generating that error message.

    It looks like the sender's mail server does not allow your server to connect and do an actual callout to verify the existence of the sender's email address. That's a configuration issue on the end of the sender's mail server. However, you'll find a lot of servers across the internet that do not allow callouts. Strangely enough, you'll find a lot of servers on the internet who REQUIRE that YOU allow THEM to perform callouts to YOUR server... go figure.

    Yes, callouts probably have to be disabled by any Cpanel host who really cares about their customer's mail being delivered.

    In fact, there is even a damned blacklist that somebody put up now that adds servers who DO callouts - claiming that it is an abuse of the server that is having the callout performed on it.

    Mike
     
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