non delivered email messages

  1. my wordpress can not send emails. It says SENDMAIL was wrong or not available.
  2. Some customers don’t get emails from my server after placing orders (opencart). I went to roundcube where I found many emails rejected by the recepient server with this message in it…>: host[] said: 550 5.1.0 Invalid
sender domain (in reply to MAIL FROM command)

thank you!

What distribution are you using? Are you using Virtualmin? Do you have Postfix installed?

If Ubuntu/Debian and Postfix is available: What output do you get for the command hostname and hostname -f? What’s in your file /etc/mailname? What’s the output of postconf -n?

(When you post shell listings, please enclose them in [code][/code] tags.)

Q: What distribution are you using? Are you using Virtualmin? Do you have Postfix installed?
A: latest CentOS

hostname >> CentOS-65-64-minimal
hostname -f >> CentOS-65-64-minimal

/etc/mailname >> no such file or directory

postconf -n

alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
allow_percent_hack = no
broken_sasl_auth_clients = yes
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/libexec/postfix
data_directory = /var/lib/postfix
debug_peer_level = 2
home_mailbox = Maildir/
html_directory = no
inet_interfaces = all
inet_protocols = all
mail_owner = postfix
mailbox_command = /usr/bin/procmail-wrapper -o
mailbox_size_limit = 0
mailq_path = /usr/bin/mailq.postfix
manpage_directory = /usr/share/man
mydestination = $myhostname, localhost.$mydoma
newaliases_path = /usr/bin/newaliases.postfix
queue_directory = /var/spool/postfix
readme_directory = /usr/share/doc/postfix-2.6.
sample_directory = /usr/share/doc/postfix-2.6.
sender_bcc_maps = hash:/etc/postfix/bcc
sendmail_path = /usr/sbin/sendmail.postfix
setgid_group = postdrop
smtpd_recipient_restrictions = permit_mynetwor
smtpd_sasl_auth_enable = yes
smtpd_sasl_security_options = noanonymous
unknown_local_recipient_reject_code = 550
virtual_alias_maps = hash:/etc/postfix/virtual

Okay, the hostname results are probably your problem. Your system needs an externally resolvable valid FQDN (fully qualified domain name). hostname should return something like “myserver”, and hostname -f should return “”.

Otherwise when destination mailservers try to check the domain of the delivering system, they stumble over the invalid hostname you have now and refuse mail.

You need to get a valid FQDN and assign it properly to your server. Unfortunately I don’t know which files to edit under CentOS for that (Ubuntu/Debian guy myself), but Eric should know.

You should also properly configure the reverse DNS entry for your server, so that your IP resolved to the hostname your Postfix presents. This is usually done at your hoster’s control panel.

Alright thank a lot for all this and let’s hope Eric will take over to guide me tthrough the process.
thank you again

Yes I have Postfix installed and I set the “What domain to use in outbound mail” to “Use domainname”
I am hosting more than one domain.

Eric where are you? :slight_smile:


To set your hostname, you can use Webmin for that. Just click Webmin -> Networking -> Network Configuration -> Hostname and DNS Client.


I changed the hostname from CentOS-65-64-minimal to a different one (I don’t even know why I had to) and now I can’t even receive emails to non of the email addresses set on any of the virtual servers accounts.

Please get abck to me asap!

PS: Pelase read this topic from the beginning. thank you

Just to make it clear… the messages sent from my gmail to my domain names mail accounts don’t evern get to the server (webmin > Read User Mail). Mailboxes are empty

I am getting bounces to gmail with the following

Host or domain name not found. Name service error for
name=localdomain.localdomain type=AAAA: Host not found


You may want to make sure your hostname exists on the “mydestination” line of /etc/postfix/ If you modify that file, make sure you restart Postfix afterwards.

You can use the email logs in /var/log/maillog to assist you in tracking down any problems if you continue to have issues.


Ok this is getting heavy for me…

I have changed the hostname to gggroup
#hostname = gggroup

then I added the domain name to the /etc/sysconfig/network so…

I restarted the network

#hostname -f results in
hostname: Unknown host

I can reach my website via browser through my IP address.

Eric, please help me out. My email system is completely down.
thanks a lot

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

this is what I get when I send email to any of the addresses hosted on my server