Our system has detected that this message is 550-5.7.1 likely unsolicited mail

Hi
The mail server (MailInABox v57a) has encountered a problem with delivering mail to Gmail.
For example the header of a sending a mail is as below:

Return-Path: <>
Delivered-To: Ali@iauh.ac.ir
Received: from box.mail1.iauh.ac.ir ([127.0.0.1])
    by box.mail1.iauh.ac.ir with LMTP id UEmiGboAQWOfNAAAb6PZRg
    for <Ali@iauh.ac.ir>; Sat, 08 Oct 2022 08:16:50 +0330
X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on box.mail1.iauh.ac.ir
X-Spam-Level:
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,NO_RELAYS,
    URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.2
X-Spam-Report:
    * -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1%
    * [score: 0.0000]
    * 0.0 URIBL_BLOCKED ADMINISTRATOR NOTICE: The query to URIBL was
    * blocked. See
    * http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block
    * for more information.
    * [URIs: iauh.ac.ir]
    * -0.0 NO_RELAYS Informational: message was not relayed via SMTP
X-Spam-Score: -1.9
Received: by box.mail1.iauh.ac.ir (Postfix)
    id 5DC068C1314; Sat, 8 Oct 2022 08:16:50 +0330 (+0330)
Date: Sat, 8 Oct 2022 08:16:50 +0330 (+0330)
From: MAILER-DAEMON@box.mail1.iauh.ac.ir (Mail Delivery System)
Subject: Undelivered Mail Returned to Sender
To: Ali@iauh.ac.ir
Auto-Submitted: auto-replied
MIME-Version: 1.0
Content-Type: multipart/report; report-type=delivery-status;
    boundary="B29AB8C12E7.1665204410/box.mail1.iauh.ac.ir"
Message-Id: <20221008044650.5DC068C1314@box.mail1.iauh.ac.ir>

The result of MXToolbox check can be accessible from Link

Please guide me.

You can try Google postmaster and see if you can resolve it that way. Another delivery check is mail-tester.

There doesn’t seem to be anything in that header having to do with Gmail, so if that message were actually directed at a Google server I would expect them to reject it.

@amin You possibly do not have DNS set up properly for your MiaB instance.

How is Google involved here in your question? You are sending an email from your MiaB to a domain hosted on your MIaB, so I am not sure where you think Google comes in.

Perhaps you are meaning to say that when you send an email to Google they not accepting it and you just gave us the wrong mail delivery failure notice to look at??

Let us see the mail delivery failure notice for the mail in question please.

Regarding your DNS, what is the purpose of the second MX record pointing to mail.iauh.ac.ir?

Hi thank you for replying
the above header is an example of mail that received when I send any mail to Gmail. the original header of mail when sent to Gmail is as below:

MIME-Version: 1.0
Date: Mon, 10 Oct 2022 08:36:53 +0330
From: Ali@iauh.ac.ir
To: amin irandoost <Amin.Irandoost@gmail.com>
Subject: test
Message-ID: <333cd6bb6ddc89aeadbf45020d37d737@iauh.ac.ir>
X-Sender: Ali@iauh.ac.ir
Content-Type: text/plain; charset=US-ASCII;
    format=flowed
Content-Transfer-Encoding: 7bit

you can see the result of mail-tester from link

Hi thank you for replying
Yes my problem is mail delivery to gmail. Gmail rejected my MiaB mail with error number 550-5.7.1

mail.iauh.ac.ir is an older server and currently is not used.

Hi thank you for replying
Yes my problem is mail delivery to gmail. Gmail rejected my MiaB mail with error number 550-5.7.1

mail.iauh.ac.ir is an older server and currently is not used.

Please share the mail delivery failure notice. Outgoing headers are meaningless. @amin

Never ever send an email to Google with the subject ‘test’. I sincerely hope that you had a good message for if the message is simply ‘test’ Google will both reject the message and your domain reputation will take a massive hit.

This is the mail system at host box.mail1.iauh.ac.ir.

I’m sorry to have to inform you that your message could not
be delivered to one or more recipients. It’s attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

The mail system

<Amin.Irandoost@gmail.com>: host gmail-smtp-in.l.google.com[74.125.128.26]
said: 550-5.7.1 [87.107.47.60 12] Our system has detected that this
message is 550-5.7.1 likely unsolicited mail. To reduce the amount of spam
sent to Gmail, 550-5.7.1 this message has been blocked. Please visit
550-5.7.1 Why has Gmail blocked my messages? - Gmail Help 550
5.7.1 for more information.
hg3-20020a1709072cc300b0078d7790fefdsi7462396ejc.927 - gsmtp (in reply to
end of DATA command)

Reporting-MTA: dns; box.mail1.iauh.ac.ir
X-Postfix-Queue-ID: 72B718C135E
X-Postfix-Sender: rfc822; amin.irandoost@iauh.ac.ir
Arrival-Date: Mon, 10 Oct 2022 08:36:53 +0330 (+0330)

Final-Recipient: rfc822; Amin.Irandoost@gmail.com
Original-Recipient: rfc822;Amin.Irandoost@gmail.com
Action: failed
Status: 5.7.1
Remote-MTA: dns; gmail-smtp-in.l.google.com
Diagnostic-Code: smtp; 550-5.7.1 [87.107.47.60 12] Our system has detected
that this message is 550-5.7.1 likely unsolicited mail. To reduce the
amount of spam sent to Gmail, 550-5.7.1 this message has been blocked.
Please visit 550-5.7.1
Why has Gmail blocked my messages? - Gmail Help 550 5.7.1 for
more information. hg3-20020a1709072cc300b0078d7790fefdsi7462396ejc.927 -
gsmtp

salam test mikonam

Try sending a real message. @amin

Subject: Tomorrow’s dinner
Body: Just want to confirm that we are meeting for dinner tomorrow, correct?

This is the mail system at host box.mail1.iauh.ac.ir.

I’m sorry to have to inform you that your message could not
be delivered to one or more recipients. It’s attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

The mail system

<Amin.Irandoost@gmail.com>: host gmail-smtp-in.l.google.com[173.194.69.27]
said: 550-5.7.1 [87.107.47.60 12] Our system has detected that this
message is 550-5.7.1 likely unsolicited mail. To reduce the amount of spam
sent to Gmail, 550-5.7.1 this message has been blocked. Please visit
550-5.7.1 Why has Gmail blocked my messages? - Gmail Help 550
5.7.1 for more information.
hs10-20020a1709073e8a00b0072f38ecf74asi11887143ejc.794 - gsmtp (in reply to
end of DATA command)

Reporting-MTA: dns; box.mail1.iauh.ac.ir
X-Postfix-Queue-ID: 2E8A58C10E6
X-Postfix-Sender: rfc822; amin.irandoost@iauh.ac.ir
Arrival-Date: Tue, 11 Oct 2022 22:52:21 +0330 (+0330)

Final-Recipient: rfc822; Amin.Irandoost@gmail.com
Original-Recipient: rfc822;Amin.Irandoost@gmail.com
Action: failed
Status: 5.7.1
Remote-MTA: dns; gmail-smtp-in.l.google.com
Diagnostic-Code: smtp; 550-5.7.1 [87.107.47.60 12] Our system has detected
that this message is 550-5.7.1 likely unsolicited mail. To reduce the
amount of spam sent to Gmail, 550-5.7.1 this message has been blocked.
Please visit 550-5.7.1
Why has Gmail blocked my messages? - Gmail Help 550 5.7.1 for
more information. hs10-20020a1709073e8a00b0072f38ecf74asi11887143ejc.794 -
gsmtp

Subject Tomorrow’s dinner
From amin.irandoost@iauh.ac.ir
To amin irandoost Amin.Irandoost@gmail.com
Date Today 22:52

Just want to confirm that we are meeting for dinner tomorrow, correct?

First off get yourself removed from this blacklist.

https://matrix.spfbl.net/87.107.47.60

Reputation tools such as Talos Intelligence show that there has been a lot of spam coming from your IP in the previous month. Perhaps you may need to request a new IP address from your provider. You may also want to sign up for Google Postmaster Tools.

I did it.
The IP 87.107.47.60 was already delisted.

How long ago? It is still listed as of 10 seconds ago. Perhaps they have a waiting period before delisting?

@amin thank you for sharing the solutions