I get "Undelivered Mail" 550-5.1.1 for non existent users

deno · December 8, 2022, 1:29am

Hello all,

i’ve tried to set up cyberpanel and email server. Everything is working fine, i do receive E-Mails and i can send them. But there is one thing i can’t solve.

When i send an email to my email adress configured in cyberpanel, i receive “Undelivered Mail Returned to Sender”:


This is the mail system at host domain.com . 

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 

<--@domain.com > (expanded from <-->): bad address syntax 

<-@domain.com > (expanded from <->): bad address syntax 

<flags=Rq@domain.com > (expanded from <flags=Rq>): user unknown 

<user@domain.com userpipe>: Host or domain name not found. Name service error for 
name=domain.com userpipe type=AAAA: Host not found 

<user=besen8111@domain.com > (expanded from <user=besen8111>): user unknown 

<pipe@domain.com > (expanded from <pipe>): user unknown 

<unix@domain.com > (expanded from <unix>): user unknown 

<argv=domain.com@gmail.com>: host gmail-smtp-in.l.google.com[173.194.76.26] 
said: 550-5.1.1 The email account that you tried to reach does not exist. 
Please try 550-5.1.1 double-checking the recipient's email address for 
typos or 550-5.1.1 unnecessary spaces. Learn more at 550 5.1.1 
https://support.google.com/mail/?p=NoSuchUser 
n23-20020a7bc5d7000000b003b4fc79e442si1817680wmk.202 - gsmtp (in reply to 
RCPT TO command) 

<n@domain.com > (expanded from <n>): user unknown 

<-f@domain.com > (expanded from <-f>): bad address syntax 
Reporting-MTA: dns; domain.com 
X-Postfix-Queue-ID: 862432398A1
X-Postfix-Sender: rfc822; mymail@gmx.de
Arrival-Date: Thu,  8 Dec 2022 01:14:49 +0000 (UTC)

Final-Recipient: rfc822; --@domain.com 
Original-Recipient: rfc822;--@domain.com 
Action: failed
Status: 5.1.3
Diagnostic-Code: X-Postfix; bad address syntax

Final-Recipient: rfc822; -@domain.com 
Original-Recipient: rfc822;-@domain.com 
Action: failed
Status: 5.1.3
Diagnostic-Code: X-Postfix; bad address syntax

Final-Recipient: rfc822; flags=Rq@domain.com 
Original-Recipient: rfc822;flags=Rq@domain.com 
Action: failed
Status: 5.1.1
Diagnostic-Code: x-unix; user unknown

Final-Recipient: rfc822; user@domain.com userpipe
Original-Recipient: rfc822;user@domain.com userpipe
Action: failed
Status: 5.4.4
Diagnostic-Code: X-Postfix; Host or domain name not found. Name service error
   for name=domain.com userpipe type=AAAA: Host not found

Final-Recipient: rfc822; user=besen8111@domain.com 
Original-Recipient: rfc822;user=besen8111@domain.com 
Action: failed
Status: 5.1.1
Diagnostic-Code: x-unix; user unknown

Final-Recipient: rfc822; pipe@domain.com 
Original-Recipient: rfc822;pipe@domain.com 
Action: failed
Status: 5.1.1
Diagnostic-Code: x-unix; user unknown

Final-Recipient: rfc822; unix@domain.com 
Original-Recipient: rfc822;unix@domain.com 
Action: failed
Status: 5.1.1
Diagnostic-Code: x-unix; user unknown

Final-Recipient: rfc822; argv=domain.com@gmail.com
Original-Recipient: rfc822;argv=domain.com@gmail.com
Action: failed
Status: 5.1.1
Remote-MTA: dns; gmail-smtp-in.l.google.com
Diagnostic-Code: smtp; 550-5.1.1 The email account that you tried to reach does
   not exist. Please try 550-5.1.1 double-checking the recipient's email
   address for typos or 550-5.1.1 unnecessary spaces. Learn more at 550 5.1.1
   https://support.google.com/mail/?p=NoSuchUser
   n23-20020a7bc5d7000000b003b4fc79e442si1817680wmk.202 - gsmtp

Final-Recipient: rfc822; n@domain.com 
Original-Recipient: rfc822;n@domain.com 
Action: failed
Status: 5.1.1
Diagnostic-Code: x-unix; user unknown

Final-Recipient: rfc822; -f@domain.com 
Original-Recipient: rfc822;-f@domain.com 
Action: failed
Status: 5.1.3
Diagnostic-Code: X-Postfix; bad address syntax

This is the E-Mail Error Log:

Error		
Dec  8 00:39:12 ws postfix/qmgr[10427]: B3147239907: from=<mymail@gmx.de>, size=11865, nrcpt=1 (queue active)
Dec  8 00:39:12 ws spamd[910]: spamd: connection from ::1 [::1]:45140 to port 783, fd 5
Dec  8 00:39:12 ws spamd[910]: spamd: setuid to spamd succeeded
Dec  8 00:39:12 ws spamd[910]: spamd: creating default_prefs: /var/log/spamassassin/.spamassassin/user_prefs
Dec  8 00:39:12 ws spamd[910]: config: cannot create user preferences file /var/log/spamassassin/.spamassassin/user_prefs: No such file or directory
Dec  8 00:39:12 ws spamd[910]: spamd: failed to create readable default_prefs: /var/log/spamassassin/.spamassassin/user_prefs
Dec  8 00:39:12 ws spamd[910]: spamd: processing message <trinity-4c481820-de51-4150-a787-3892d47b0406-1670459945320@msvc-mesg-gmx025> for spamd:5002
Dec  8 00:39:12 ws MailScanner[2191]: Deleted 1 messages from processing-database
Dec  8 00:39:12 ws MailScanner[2191]: MailWatch: Logging message B6A42239902.AE7C1 to SQL
Dec  8 00:39:12 ws MailWatch SQL[2165]: B6A42239902.AE7C1: Logged to MailWatch SQL
Dec  8 00:39:16 ws spamd[910]: plugin: eval failed: bayes: (in learn) locker: safe_lock: cannot create tmp lockfile /var/log/spamassassin/.spamassassin/bayes.lock.ws.besenic.de.910 for /var/log/spamassassin/.spamassassin/bayes.lock: No such file or directory
Dec  8 00:39:16 ws spamd[910]: spamd: clean message (-0.1/5.0) for spamd:5002 in 4.0 seconds, 11995 bytes.
Dec  8 00:39:16 ws spamd[910]: spamd: result: . 0 - DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,HTML_MESSAGE,MIME_HTML_ONLY,RCVD_IN_MSPIKE_H2,RCVD_IN_ZEN_BLOCKED_OPENDNS,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,URIBL_DBL_BLOCKED_OPENDNS,URIBL_ZEN_BLOCKED_OPENDNS scantime=4.0,size=11995,user=spamd,uid=5002,required_score=5.0,rhost=::1,raddr=::1,rport=45140,mid=<trinity-4c481820-de51-4150-a787-3892d47b0406-1670459945320@msvc-mesg-gmx025>,autolearn=unavailable autolearn_force=no
Dec  8 00:39:16 ws postfix/pipe[10527]: B3147239907: to=<user@domain.com >, relay=spamassassin, delay=11, delays=7.2/0.01/0/4, dsn=2.0.0, status=sent (delivered via spamassassin service)
Dec  8 00:39:16 ws postfix/pickup[10426]: EF1D5239909: uid=5002 from=<mymail@gmx.de>
Dec  8 00:39:16 ws postfix/qmgr[10427]: B3147239907: removed
Dec  8 00:39:17 ws spamd[838]: prefork: child states: II
Dec  8 00:39:17 ws postfix/cleanup[10514]: EF1D5239909: hold: header Received: by domain.com  (Postfix, from userid 5002)??id EF1D5239909; Thu,  8 Dec 2022 00:39:16 +0000 (UTC) from local; from=<mymail@gmx.de> to=<user@domain.com >
Dec  8 00:39:17 ws postfix/cleanup[10514]: EF1D5239909: message-id=<trinity-4c481820-de51-4150-a787-3892d47b0406-1670459945320@msvc-mesg-gmx025>
Dec  8 00:39:17 ws opendkim[7181]: EF1D5239909: DKIM verification successful
Dec  8 00:39:17 ws opendkim[7181]: EF1D5239909: s=s31663417 d=gmx.de a=rsa-sha256 SSL 
Dec  8 00:39:17 ws MailScanner[2168]: New Batch: Scanning 1 messages, 14097 bytes
Dec  8 00:39:18 ws MailScanner[2168]: Virus and Content Scanning: Starting
Dec  8 00:39:18 ws MailScanner[2168]: SpamAssassin cache hit for message EF1D5239909.A0E0E
Dec  8 00:39:18 ws MailScanner[2168]: Requeue: EF1D5239909.A0E0E to 74B30239902
Dec  8 00:39:18 ws MailScanner[2168]: Uninfected: Delivered 1 messages
Dec  8 00:39:18 ws postfix/qmgr[10427]: 74B30239902: from=<mymail@gmx.de>, size=12791, nrcpt=12 (queue active)
Dec  8 00:39:18 ws postfix/error[10544]: 74B30239902: to=<--@domain.com >, orig_to=<-->, relay=none, delay=1.4, delays=1.4/0.01/0/0.01, dsn=5.1.3, status=bounced (bad address syntax)
Dec  8 00:39:18 ws MailScanner[2168]: Deleted 1 messages from processing-database
Dec  8 00:39:18 ws postfix/smtp[10545]: 74B30239902: to=<user@domain.com denopipe>, relay=none, delay=1.4, delays=1.4/0.02/0/0, dsn=5.4.4, status=bounced (Host or domain name not found. Name service error for name=domain.com denopipe type=AAAA: Host not found)
Dec  8 00:39:18 ws MailScanner[2168]: MailWatch: Logging message EF1D5239909.A0E0E to SQL
Dec  8 00:39:18 ws postfix/pipe[10546]: 74B30239902: to=<flags=rq@domain.com >, orig_to=<flags=Rq>, relay=dovecot, delay=1.4, delays=1.4/0.01/0/0.03, dsn=5.1.1, status=bounced (user unknown)
Dec  8 00:39:18 ws postfix/smtp[10551]: connect to gmail-smtp-in.l.google.com[2a00:1450:400c:c09::1a]:25: Network is unreachable
Dec  8 00:39:18 ws MailWatch SQL[2165]: EF1D5239909.A0E0E: Logged to MailWatch SQL
Dec  8 00:39:18 ws postfix/pipe[10560]: 74B30239902: to=<user=user@domain.com >, orig_to=<user=besen8111>, relay=dovecot, delay=1.4, delays=1.4/0.05/0/0.02, dsn=5.1.1, status=bounced (user unknown)
Dec  8 00:39:18 ws postfix/pipe[10543]: 74B30239902: to=<user@domain.com >, relay=dovecot, delay=1.4, delays=1.4/0.01/0/0.08, dsn=2.0.0, status=sent (delivered via dovecot service)
Dec  8 00:39:18 ws postfix/pipe[10549]: 74B30239902: to=<n@domain.com >, orig_to=<n>, relay=dovecot, delay=1.4, delays=1.4/0.02/0/0.07, dsn=5.1.1, status=bounced (user unknown)
Dec  8 00:39:18 ws postfix/pipe[10552]: 74B30239902: to=<pipe@domain.com >, orig_to=<pipe>, relay=dovecot, delay=1.5, delays=1.4/0.03/0/0.07, dsn=5.1.1, status=bounced (user unknown)
Dec  8 00:39:18 ws postfix/smtp[10551]: 74B30239902: to=<argv=domain.com@gmail.com>, relay=gmail-smtp-in.l.google.com[108.177.15.27]:25, delay=1.5, delays=1.4/0.03/0.1/0.02, dsn=5.1.1, status=bounced (host gmail-smtp-in.l.google.com[108.177.15.27] said: 550-5.1.1 The email account that you tried to reach does not exist. Please try 550-5.1.1 double-checking the recipient's email address for typos or 550-5.1.1 unnecessary spaces. Learn more at 550 5.1.1  https://support.google.com/mail/?p=NoSuchUser m38-20020a05600c3b2600b003cf6748f285si2013093wms.148 - gsmtp (in reply to RCPT TO command))
Dec  8 00:39:18 ws postfix/smtp[10545]: 74B30239902: to=<mymail@gmx.de>, relay=mx00.emig.gmx.net[212.227.15.9]:25, delay=1.5, delays=1.4/0.03/0.1/0.05, dsn=2.0.0, status=sent (250 Requested mail action okay, completed: id=1Mdf3z-1oTkG71vdp-00Zjuz)
Dec  8 00:39:19 ws postfix/error[10544]: 74B30239902: to=<-@domain.com >, orig_to=<->, relay=none, delay=2.3, delays=1.4/0.01/0/0.88, dsn=5.1.3, status=bounced (bad address syntax)
Dec  8 00:39:19 ws postfix/error[10544]: 74B30239902: to=<-f@domain.com >, orig_to=<-f>, relay=none, delay=2.3, delays=1.4/0.01/0/0.89, dsn=5.1.3, status=bounced (bad address syntax)
Dec  8 00:39:19 ws postfix/pipe[10555]: 74B30239902: to=<unix@domain.com >, orig_to=<unix>, relay=dovecot, delay=2.5, delays=1.4/0.04/0/1.1, dsn=5.1.1, status=bounced (user unknown)
Dec  8 00:39:19 ws postfix/cleanup[10514]: 708AD239909: message-id=<20221208003919.708AD239909@domain.com >
Dec  8 00:39:19 ws postfix/bounce[10566]: 74B30239902: sender non-delivery notification: 708AD239909
Dec  8 00:39:19 ws postfix/qmgr[10427]: 708AD239909: from=<>, size=17482, nrcpt=1 (queue active)
Dec  8 00:39:19 ws postfix/qmgr[10427]: 74B30239902: removed
Dec  8 00:39:19 ws postfix/smtp[10558]: 708AD239909: to=<mymail@gmx.de>, relay=mx00.emig.gmx.net[212.227.15.9]:25, delay=0.22, delays=0.01/0/0.1/0.1, dsn=2.0.0, status=sent (250 Requested mail action okay, completed: id=1MKJhN-1pOKim2POh-00Ljgb)
Dec  8 00:39:19 ws postfix/qmgr[10427]: 708AD239909: removed
Dec  8 00:39:21 ws dovecot: imap-login: Login: user=<user@domain.com >, method=PLAIN, rip=46.239.6.106, lip=45.67.139.172, mpid=10570, TLS, session=<LS+XREbvv0su7wZq>

Hope somebody can help!

josephgodwinke · December 8, 2022, 6:06am

Welcome @deno Happy you are here

Is an invalid TLD check the email db@dbmedia.medennypipe it is not valid TLD at the end.

My best guess from what you provided is db@dbmedia.me

Your DNS records seem ok. Have you tried https://www.mail-tester.com/. Post a screenshot of your score for spammyness

josephgodwinke · December 8, 2022, 9:09am

Reverse DNS is not a valid Hostname

Your reverse (PTR) record:
172.139.67.45.in-addr.arpa → dbmedia.me it should be mail.dbmedia.me or your hostname such as panel.dbmedia.me/host.dbmedia.me etc.

Let’s say you want your users to access the CyberPanel panel via switch.dbmedia.me create a website with no mail or ssl. Then issue hostname ssl to switch.dbmedia.me via SSL > Hostname SSL

In ssh terminal nano /usr/local/lsws/conf/httpd_config.conf

Paste following content:

extprocessor cyberpanel {
  type                    proxy
  address                 https://switch.dbmedia.me:8090
  maxConns                100
  pcKeepAliveTimeout      60
  initTimeout             60
  retryTimeout            0
  respBuffer              0
}

Then reverse proxy using Rewrite Rules 6 - Rewrite Rules - 04 - Websites - CyberPanel Community by adding this

REWRITERULE ^(.*)$ HTTP://cyberpanel/$1 [P]

FInally run hostname switch.dbmedia.me and also set PTR for your VPS in your DNS Manager with your service provder chnage ipv4 and ipv6 records to switch.dbmedia.me

Psst its best you set rDNS to mail.dbmedia.me

deno · December 9, 2022, 12:05am

Thank you very much for your reply.

I found the problem, it was a misconfiguration in the last line of the postfix master.cf in /etc/postfix/master.cf. The lines were not separated as they should be.

This caused a problem with spamassassin trying to deliver the mails to the named “users”.

I don’t know how this happened, but I did a fresh install. Something must have gone wrong with it.

system · December 9, 2022, 3:05am

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