The email message could not be delivered because of an unknown issue

knightmare

Active Member
May 31, 2018
28
2
3
India
cPanel Access Level
Root Administrator
Hello there,

I have some problem with send mail.
Code:
This message was created automatically by mail delivery software.
A message that you sent has not yet been delivered to one or more of its
recipients after more than 48 hours on the queue on host.example.com.

The message identifier is:     1gla84-0003t7-JW
The subject of the message is: my subject
The date of the message is:    Mon, 21 Jan 2019 19:31:05 +0530

The addresses to which the message has not yet been delivered are:

  [email protected]
  [email protected]

No action is required on your part. Delivery attempts will continue for
some time, and this warning may be repeated at intervals if the message
remains undelivered. Eventually the mail delivery software will give up,
and when that happens, the message will be returned to you.


Reporting-MTA: dns; host.domain.com

Action: delayed
Final-Recipient: rfc822;[email protected]
Status: 4.0.0

Action: delayed
Final-Recipient: rfc822;[email protected]
Status: 4.0.0


Return-path: <[email protected]>
Received: from [some-ip] (port=30906 helo=[my-ip])
    by host.domain.com with esmtpa (Exim 4.91)
    (envelope-from <[email protected]>)
    id 1gla84-0003t7-JW; Mon, 21 Jan 2019 19:30:44 +0530
To: [email protected], [email protected]
Cc: some-one <[email protected]>,

From: ME <[email protected]>
Subject: my subject
Message-ID: <[email protected]>
Date: Mon, 21 Jan 2019 19:31:05 +0530
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.2.1
MIME-Version: 1.0
Content-Type: multipart/alternative;
 boundary="------------9A8B70A0B44D5CDF9F932078"
Content-Language: en-US
How to fix it?
 
Last edited by a moderator:

rpvw

Well-Known Member
Jul 18, 2013
1,101
470
113
UK
cPanel Access Level
Root Administrator
4.0.0 Email Bounce Error:

Delayed Message: Unknown issue
The email message could not be delivered because of an unknown issue.

Fixes
  • Check the recipient's email for misspellings or missing letters.
  • Check your mail logs for any hints as to why the delivery failed on previous delivery attempts

4.0.0: Official Definition

[RFC3463] (Standards Track) from the The Internet Engineering Task Force (IETF) definition for codes that start with 4.X.X:
A persistent transient failure is one in which the message as sent is valid, but persistence of some temporary condition has caused abandonment or delay of attempts to send the message. If this code accompanies a delivery failure report, sending in the future may be successful.

[RFC3463] (Standards Track) from the The Internet Engineering Task Force (IETF) definition for codes that end with X.0.0:
Other undefined status is the only undefined error code. It should be used for all errors for which only the class of the error is known.[/SIZE]
 
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cPanelLauren

Product Owner II
Staff member
Nov 14, 2017
13,274
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Houston
The advice provided here by @rpvw is on point, it would seem there's an issue with the email address. If you have root access to the server checking the exim logs may provide some insight to what happened. You can find the exim logs here:
Code:
/var/log/exim_mainlog
 

rpvw

Well-Known Member
Jul 18, 2013
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470
113
UK
cPanel Access Level
Root Administrator
The error you posted does not tell us what the original reason for the delivery failure was. It only tells us that the retry time has not been reached to try again.

The post below should help you:

Can you try to see if you can connect to the port 25 of remote mail server from the server itself ?

dig mx domain.com (the domain name is the domain of email account failing ) to get the mail servers. Then try telnet to the mail server to see if you can connect from the server. If no , some firewall block either at your server , or at the remote server is causing the problem.
 

knightmare

Active Member
May 31, 2018
28
2
3
India
cPanel Access Level
Root Administrator
[email protected]:~$ dig mx domain.com

OUTPUT :-

; <<>> DiG 9.11.3-1ubuntu1.3-Ubuntu <<>> mx domain.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 56922
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;domain.com. IN MX

;; ANSWER SECTION:
domain.com. 599 IN MX 1 host.domain.com.
domain.com. 599 IN MX 2 mail.domain.com.

;; Query time: 78 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
;; WHEN: Wed Jan 30 14:38:20 IST 2019
;; MSG SIZE rcvd: 90

TELNET :-

[email protected]:~$ telnet mail.domain.com 25
Trying 111.111.111.111...
Connected to domain.com.
Escape character is '^]'.
220-host.domain.com ESMTP Exim 4.91 #1 Wed, 30 Jan 2019 14:42:34 +0530
220-We do not authorize the use of this system to transport unsolicited,
220 and/or bulk e-mail.
quit
221 host.domain.com closing connection
Connection closed by foreign host.

Is this ok ?
 

rpvw

Well-Known Member
Jul 18, 2013
1,101
470
113
UK
cPanel Access Level
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; <<>> DiG 9.11.3-1ubuntu1.3-Ubuntu <<>> mx domain.com
I didn't think that cPanel could be run off Ubuntu ? :confused:

Have you tried to force the delivery from the mail queue manager ? and if so, what errors did it show ?
 

cPanelLauren

Product Owner II
Staff member
Nov 14, 2017
13,274
1,292
313
Houston
At this point, if you're not having the issue with any other domains, my assumption would be that there's an issue with your mail server reaching the destination mail server. It could be a number of things if they have a postmaster or help center they should be able to tell you specifically why mail is being deferred.
 

rpvw

Well-Known Member
Jul 18, 2013
1,101
470
113
UK
cPanel Access Level
Root Administrator
We are not terribly interested if your local system can successfully resolve the MX records of the target domain !

You need to know if your server can resolve them, and then if you can telnet to it from your server o_O
 

cPanelLauren

Product Owner II
Staff member
Nov 14, 2017
13,274
1,292
313
Houston
I have tested with my local system and that is Ubuntu. :D
ok, tell me how to solve this error ?
It's irrelevant, as the connection issue exists between your server and the recipient server. As I stated previously if you're not experiencing an issue sending to other domains it sounds a lot like the issue needs to be addressed at the recipient server.

Thanks!