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SMTP 451-Could not complete sender verify callout

Discussion in 'General Discussion' started by cmonego, Nov 14, 2017.

  1. cmonego

    cmonego Member

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    Hello,

    I am facing a problem on my server. I have a client that receives emails with a sender that does not exist (example@example.test.com). The sender is masked. I was able to resolve the incoming issue by disabling Exim's "use callout to check" function. But I would like to know if there is any way for my client to be able to respond to these messages because the current form is not working.

    Thank's

    []s
     
  2. cPanelMichael

    cPanelMichael Technical Support Community Manager
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    Hello,

    What error message do you see in /var/log/exim_mainlog during the attempt to respond to the email? EX:

    Code:
    exigrep user@domain /var/log/exim_mainlog
    Thank you.
     
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  3. cmonego

    cmonego Member

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    Hi Michael,

    Log Message error:

    2017-11-13 12:18:22 1eEFAY-0006O0-NO == [removed] R=lookuphost defer (-1): host lookup did not complete


    I receive messages from this sender, but I can not reply to them. Is there any way to adjust this?

    []'s
     
  4. cPanelMichael

    cPanelMichael Technical Support Community Manager
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    Hello,

    That error suggests the domain name the user is sending the message to does not exist or does not resolve to a valid IP address. Thus, there's no way for Exim to route the message. Are you sure that it's a valid domain name?

    Thank you.
     
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  5. cmonego

    cmonego Member

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    Exactly,

    The domain [removed] exists. However, messages are sent in this format, as shown in the previous LOG. Now I get messages, but I can not respond, just because the search was not completed. The client is saying that in Gmail it works, so I went to the Forum to see if there is any way to configure to receive / reply to messages from that domain.
     
    #5 cmonego, Nov 14, 2017
    Last edited by a moderator: Nov 14, 2017
  6. cPanelMichael

    cPanelMichael Technical Support Community Manager
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    Hello,

    Access your server as root via SSH and see if your server can connect to that remote server. EX:

    Code:
    host $remote-domain
    telnet $remote-domain 25
    Thank you.
     
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