Issue Emails are not delivered nor received

[Patashoow]

Server operating system version

Ubuntu 20.04

Plesk version and microupdate number

18.0.47

Hello,

I have Plesk Obsidian 18.0.47 with Ubuntu 20.04 and I'm having huge problems with emails.

I don't really know where to start as I'm quite new to server configurations.

When I try to send an email (either with Roundcube or from a script), the email is sent but never received by the recipient. When I check the queue, it first says "Active messages queue" and then "Deferred messages queue".

When I try to send an email from an external email address (hotmail for example) to my own email address related to my domain, I have the following error message "Remote server returned unknown recipient or mailbox unavailable".

I don't know if it has something to do with DNS configuration or is it about something else but at this point, any help is welcome.

Thanks.

 

[IgorG]

If you have any problems with your emails, you should first examine the main Plesk mail log file /var/log/maillog for error records related to the problem.
Sometimes the command to fix the mail settings can help:

# plesk repair mail

 

[Patashoow]

Thank you for your reply. I've just checked the maillog file and it's empty.

There's also one thing, when I compare DNS records in Plesk and those in my host panel, they are a bit different so is it normal?

 

[Patashoow]

Sorry my bad I checked the wrong file.

So all the logs are saying "connection timed out"

 

[IgorG]

So all the logs are saying "connection timed out"

Perhaps there is something wrong with DNS configuration that hostnames can't be correctly resolved.

 

[Patashoow]

Yes that's what I'm suspecting especially when I compare the records in Plesk and those in my host panel. Is there anything I can refer to to get the configuration right?

 

[Patashoow]

I have matched the DNS records of Plesk and those in my host panel and now, emails can be received but they can only be sent to local addresses. When I try to send to a Hotmail address for example, it stays in the queue and never get delivered.
When I check the logs there's still the same problem saying : "Connection timed out".
All SMTP, Imap, POP ports are open.

I really don't know what to do anymore. What could be the problem?

 

[IgorG]

Could you please provide a related error message from the maillog at least?
If you are not familiar with DNS settings, I suggest you contact Plesk Support Team, and experienced supporters will check it directly on your server.

How to get support directly from Plesk?

Question How to get support directly from Plesk? Answer Lease-type Plesk licenses purchased directly from Plesk running on supported Plesk version include full free support. Perpetual-type license...

support.plesk.com

 

[Patashoow]

Hello and thank you for your reply.

So here are the logs when I tried to send an email from a PHP script to a hotmail address:

Nov 15 03:57:30 {HOSTNAME} plesk-sendmail[1222811]: S1222811: from=<[email protected]> to=<*******@hotmail.com>
Nov 15 03:57:30 {HOSTNAME} plesk-sendmail[1222812]: S1222811: add-from: stderr: PASS
Nov 15 03:57:31 {HOSTNAME} plesk-sendmail[1222812]: S1222811: py-limit-out: stderr: INFO:__main__:Setting 'X-PPP-Vhost' header to 'domain.tld'
Nov 15 03:57:31 {HOSTNAME} plesk-sendmail[1222812]: S1222811: py-limit-out: stderr: PASS
Nov 15 03:57:31 {HOSTNAME} plesk-sendmail[1222812]: S1222811: check-quota: stderr: SKIP
Nov 15 03:57:31 {HOSTNAME} postfix/pickup[1219567]: 2893928E1AAE: uid=10001 from=<[email protected]>
Nov 15 03:57:31 {HOSTNAME} postfix/cleanup[1222822]: 2893928E1AAE: message-id=<20221115035731.2893928E1AAE@{HOSTNAME}.*********.plesk.page>
Nov 15 03:57:31 {HOSTNAME} postfix/qmgr[1207117]: 2893928E1AAE: from=<[email protected]>, size=500, nrcpt=1 (queue active)
Nov 15 03:58:01 {HOSTNAME} postfix/smtp[1222826]: connect to hotmail-com.olc.protection.outlook.com[104.47.18.97]:25: Connection timed out
Nov 15 03:58:31 {HOSTNAME} postfix/smtp[1222826]: connect to hotmail-com.olc.protection.outlook.com[104.47.17.97]:25: Connection timed out
Nov 15 03:58:31 {HOSTNAME} postfix/smtp[1222826]: 2893928E1AAE: to=<*******@hotmail.com>, relay=none, delay=60, delays=0.03/0.01/60/0, dsn=4.4.1, status=deferred (connect to hotmail-com.olc.protection.outlook.com[104.47.17.97]:25: Connection timed out)

I will also try to get direct support from Plesk (thank you for letting me know that).

 

[IgorG]

connect to hotmail-com.olc.protection.outlook.com[104.47.18.97]:25: Connection timed out

Looks like that connection to port 25 for hotmail-com.olc.protection.outlook.com hostname is firewalled.
On my test Plesk server, it is open, and I see the following:

# nc -zvw3 hotmail-com.olc.protection.outlook.com 25
hosthotmail-com.olc.protection.outlook.com [104.47.57.161] 25 (smtp) open

Have you checked your firewall settings?

 

[Patashoow]

I only have access to those settings on my host panel and I have enabled all the necessary ports.

Am I missing something?

 

[IgorG]

Try to completely disable the firewall for testing purposes and check email operation.

 

[Patashoow]

It seems that I can't disable the firewall (at least from my host panel). When I check Ubuntu firewall status, it's already disabled.

 

[AYamshanov]

I don't really know where to start as I'm quite new to server configurations.

Sorry my bad I checked the wrong file.

My two cents; I suggest using the Log Browser extension ("Tools & Settings" / "Log Browser") and the "Mail" tab for that case. Especially, If you have some sub-string for searching (e.g.: an email address or IP-address), it could provide some clue more easy and quickly for the next troubleshooting steps.



P.S. Probably, it will not help to answer the question "why connection is timed out?".

 

[Kaspar]

@Patashoow Who is your hosting provider? Some provider only open port 25 on request (or not at all). Like AWS, Google Cloud, ionos, ect. Even if you've openend port 25 on your host's Firewall, they still might block port 25.

 

[Patashoow]

@Kaspar Thank you for your reply.
I think that so far, it's the only possible reason because we have tried everything and we still have the same issue. Our host is indeed Ionos and I've just contacted them so we'll see.

 

[Patashoow]

So the port 25 was indeed blocked by Ionos. Now emails are being sent but Hotmail is blacklisting our server :

Action: failed
Status: 5.7.1
Remote-MTA: dns; hotmail-com.olc.protection.outlook.com
Diagnostic-Code: smtp; 550 5.7.1 Unfortunately, messages from [*.*.*.*]
    weren't sent. Please contact your Internet service provider since part of
    their network is on our block list (S3150). You can also refer your
    provider to http://mail.live.com/mail/troubleshooting.aspx#errors.

 

[Bitpalast]

You can check the status of your IP address in Microsoft SNDS:
Sign in to your Microsoft account

You can try to submit a case to them to get your IP off their blacklist:
Sign in to your account

 

[Patashoow]

@Peter Debik thank you for your reply.
It's quite odd as when I check the status, it says "Blocked: no" but then "Details: Junked due to user complaints or other evidence of spamming".
It's just a new IP and of what I read, they block automatically new IP addresses. But then what do the details above mean?

Anyway, I've sent a case to them and I'll be waiting for their answer.

 

[Bitpalast]

@Peter Debik thank you for your reply.
It's quite odd as when I check the status, it says "Blocked: no" but then "Details: Junked due to user complaints or other evidence of spamming".
It's just a new IP and of what I read, they block automatically new IP addresses. But then what do the details above mean?

Anyway, I've sent a case to them and I'll be waiting for their answer.

If it is a new IP, that IP is only new to you. It may have been used by a server that had sent spam in the past. By my experience at least, MS will delist an IP upon first request. It may take up to 48 hours for this to be processed, but normally it will work.