Issue Mailboxes no longer receive mail and GMail puts mail in Spam.

[CobraArbok]

Server operating system version

Ubuntu 22.04.1 LTS

Plesk version and microupdate number

18.0.49 Update #2

I haven't received any mail in any mailbox for a few days. It's not even in spam.
The sender has no error report.

Also, but I don't know if it's a related problem or different, all mail sent to a GMail mailbox ends up in spam; some other mailboxes on ISP also consider the mail as spam.

In recent days I had noticed that GMail was rejecting all mail from my mailboxes.
With the ISP (1&1) we have partially corrected the problem: now GMail receives it, but puts it in Spam.
Instead now it's my mailboxes that don't receive mail.

With www.mail-tester.com I receive these reports:
For SpamAssassin

• Message has a DKIM or DK signature, not necessarily valid. This rule is automatically applied if your email contains a DKIM signature but other positive rules will also be added if your DKIM signature is valid. See immediately below.
• Delivered to internal network by hosts with dynamic-looking rDNS
• SPF: HELO does not publish an SPF Record

Moreover

• Your message does not contain a List-Unsubscribe header

These are the screenshots of mail settings for the server and the domain:

 

[CobraArbok]

Since I can no longer edit the post, I complete the information.
Plesk is on a 1&1 VPS.
I'm using Postfix and Roundcube

Fixed the main problem, that of not receiving mail anymore, then I will also have to solve the problem with List-Unsubscribe.
To do this I have to work on Roundcube, but where do I insert the List-Unsubscribe header?

 

[Peter Debik]

You will first need to add the additional_message_headers plugin to /usr/share/psa-roundcube/config/defaults.inc.php array entry "$config['plugins']". Afterwards, the additional header needs to be inserted as a configuration line into /usr/share/psa-roundcube/config/config.inc.php like
$config['additional_message_headers']['List-Unsubscribe'] = '<mailto:sender@domain?subject=Unsubscribe>';
As always, the exact configuration depends on your requirements.

 

[CobraArbok]

You will first need to add the additional_message_headers plugin to /usr/share/psa-roundcube/config/defaults.inc.php array entry "$config['plugins']". Afterwards, the additional header needs to be inserted as a configuration line into /usr/share/psa-roundcube/config/config.inc.php like
$config['additional_message_headers']['List-Unsubscribe'] = '<mailto:sender@domain?subject=Unsubscribe>';
As always, the exact configuration depends on your requirements.

But this applies to all domains.
This may work for plugins, but the configuration must be different for each domain.

This would solve the List_Unsubscribe problem, but why am I not getting mail anymore?

 

[Peter Debik]

, but why am I not getting mail anymore?

Did you not say "Fixed the main problem, that of not receiving mail anymore,"?

I suggest to open a separate thread for each issue.

 

[CobraArbok]

You're right, I was inaccurate. Sorry.
I meant, WHEN I fix the main problem, I still need to fix the unsunscribed list problem.

In the initial post I had clarified the history of these problems.
To fix the spam report, I now have ALL mail blocked incoming.

I made the change you suggested to the plugin, but let's forget about it for now. I have to solve the main problem first.
Where can I find the incoming mail logs?

 

[Peter Debik]

All mail transactions are logged to /var/log/mail.log

 

[CobraArbok]

All mail transactions are logged to /var/log/mail.log

There is no /var/log/mail.log.
There is /var/log/maillog, mail.err and mail.processed.

In maillog I mostly see an incredible amount of login attempts, but I don't see any blocked incoming mail errors.

Mail is sent from an external mailbox, but does not arrive at any folder of the mailbox on the server.
Since there are no return errors, I have no way of understanding where it was blocked.

The ISP doesn't want to intervene because their VSP is being managed by me.
But I left the standard configuration and the few changes made are those suggested by them to prevent my mail from ending up in Google spam.

 

[Peter Debik]

Just send one test mail from a defined address and see how it shows up in your maillog file.

 

[CobraArbok]

I've already done this, several times today, but I don't see it in the log

 

[Peter Debik]

If it does not show in the log, check the MX record of the domain where you are sending mails to. Does it resolve to the IP address of your server?

 

[CobraArbok]

If it does not show in the log, check the MX record of the domain where you are sending mails to. Does it resolve to the IP address of your server?

I was thinking exactly the same thing.
For days, everyone has been telling me that the problem is on my server when maybe it's elsewhere.

 

[CobraArbok]

Testing with

MX Lookup Tool - Check your DNS MX Records online - MxToolbox

mxtoolbox.com

The domain is reported blacklisted by UCEPROTECTL3.
Which is the initial problem, from last week.
And it also reports Failed To Connect SMTP

 

[CobraArbok]

Port 25 on the ISP's firewall was closed.
Now that I've opened it, it works.
But shouldn't Plesk use port 587?

 

[Peter Debik]

Port 25 is correct.
Port 587 can be used for mail submission in combination with StartTLS. Port 465 for mail submission in combination with SSL/TLS.

 

[CobraArbok]

Port 25 is correct.
Port 587 can be used for mail submission in combination with StartTLS. Port 465 for mail submission in combination with SSL/TLS.

Isn't 25 the outgoing mail?
Why should it not allow mail to be received if it is missing?

 

[Peter Debik]

Port 25 is for incoming and outgoing mail all across the Internet. This is the port that every mailserver is listening on.

The other ports you may have heard about, 995, 993, 110, 143, 587, 465 are all ports for mail retrieval or submission, but they are not being used for inter-server-communication.

 

[CobraArbok]

Port 25 is for incoming and outgoing mail all across the Internet. This is the port that every mailserver is listening on.

The other ports you may have heard about, 995, 993, 110, 143, 587, 465 are all ports for mail retrieval or submission, but they are not being used for inter-server-communication.

For the series "I thought I knew everything and I lacked the basics"

Thank you very much. I close the ticket and I'm left with the list_unsubscribe problem