SMTP 451-Could not complete sender verify callout

cmonego

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Jul 10, 2014
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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 ([email protected]). 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
 

cPanelMichael

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Apr 11, 2011
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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.
Hello,

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

Code:
exigrep [email protected] /var/log/exim_mainlog
Thank you.
 
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cmonego

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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
 

cPanelMichael

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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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cmonego

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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.
 
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cPanelMichael

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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.