Questions tagged [email-server]
Refers to the hardware or software that make up a server dedicated to sending and receiving emails. Many popular modern email servers bundle other functionality for contacts and calendaring along email delivery.
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How to change A record in DNS and keep email working when MX record point to the domain itself
For my client, I'm migrating domain to point to a new website server. In order to do that, I'm changing A records to point to new server IP. After such change, client has lost possibility to send e-...
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Redirect local host mail to mailcow mail server ubuntu
I've installed mailcow dockerized on ubuntu 22.04 host. There is some instruction how to setup local mtu with postfix (sendmail is ubuntu default) https://docs.mailcow.email/post_installation/...
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Spamhaus blacklisted our mdaemon server IP due to wrong HELO
since two weeks ago spamhaus kept on putting our IP address on the CSS blacklist - we've had few thing to fix from the guideline so we delisted ourselves few times after checking all the requirements.
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Most Incoming Emails are not being processed by SpamAssassin
Incoming emails are mostly unchecked by SpamAssassin, although we can see in the headers that they were checked with Amavisd-new for viruses.
We've tried many things to fix it, including asking ...
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Postfix/Dovecot Not receiving external emails in Ubuntu 16.04
I have read all of the threads and can't figure out what is the problem. I can send emails. I can receive emails from my localhost and my other email names of the same domain, but I cannot receive ...
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Why is procmail saving my emails with a format like .{x}AA1?
I'm simply trying to save all incoming emails to a folder so that I can have a watchdog script comb through and parse the attachments in various ways as changes happen to the folder. We'll call this ...
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Auth/permission issues with Dovecot/Postfix with virtual users and dovecot Passwd-file
I currently have Postfix/Dovecot email-server configured to run a local system account (Dovecot auth-system) and everything runs fine with a local user set up using /etc/passwd, /etc/shadow.
I would ...
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Which domain/host to use with certificate for mail server
I am having difficulties (confused) understanding SSL for a domain for mail server. GMail "send mail as" set up is reporting error with "550 certificate name does not match host name&...
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Best Practice - SMTP Time Out
Good Day,
The question is quite straight forward. What should be a best practice to time out a SMTP connection on the RECEIVING side?
Background: We are currently having an issue with a sender that ...
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Send An E-mail To A GMAIL Address From Linux Mail Command Using Postfix As The MTA
I am a beginner in configuring mail delivery systems. Recently, orders came from the management that we need to send confirmation emails to our clients whenever they complete their applications (I ...
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Mail proxy with SPF and DMARC without changing FROM headers
Here is my situation.
We have internal network, with lots of 2nd level subdomains - foo.internal.domain.ltd as example.
Those subdomains may or may not have public DNS records with Class A IPs.
Then, ...
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Haproxy as a mail protocols reverse proxy with SSL termination
Looking for guidance of how to configure haproxy 2.4 in a container, to proxy for a mail server (all protocols, imap/s, smtp/s, pop3/s, http/s) and having haproxy doing ssl termination, but also ...
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Dovecot: doveadm sync namespace | single folder
I am trying to make sync (or sync -1) for single folder.
Forwarding the manuals, we can use -x flag to exclude folders - it works fine.
Also, there is -n flag to sync namespaces. As i see, there is no ...
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Can we determine from email headers that these two IP6 addresses came from the same person?
I'm trying to determine whether the emails came from the same office or person, but lack the in-depth knowledge of IP6 and understanding of the meaning of the same "subnet prefix".
From the ...
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Configuring Google Workspace (Gmail) to trust a Mail Relay via ARC?
I am building a system which modifies incoming emails body on the fly (for example, it deletes attachements with viruses). Of course, I break the DKIM signature when there is one. Is it possible to ...
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postfix: Configure address for MAILER-DAEMON
I have setup postfix on my Debian server to send emails (my website uses PHP Mail() to send notifications to its users).
I observe that on failed deliveries, the system tries to send the notifications ...
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How do I (automatically) re-attempt to deliver mail from a different Postfix server?
My network consists of two different locations and in both I have a Postfix server running for outgoing mail on each of them. Mail gets submitted to any of the two round-robin, based on having them ...
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Setup self-hosted mail server and route MX record from domain
I want to move away from my current email provider which also hosts my domain and setup a private mail server on my local machine which runs 24/7.
Let's say I have 4 registered email addresses user1@...
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Postfix - How to send bounces only to postmaster?
I have an internal Postfix server where bounces are intentionally discarded (not recommended in general but needed for my use case).
I would like to enable it temporarily but only to the postmaster, ...
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How to make a mail server spam "proof"
I work for a German company that sends several thousand emails to our customers every day. Our employees send their emails via Microsoft 356, but the system does not use a mail server and sends emails ...
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Changing hostname for the purpose of email delivery
I have email delivery issues, and MXtoolbox says "Reverse DNS is not a Valid Hostname". I have A and AAAA records for domain.com and mail.domain.com. The data center has set up reverse DNS ...
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A client-centric account backup and transfer option from many IMAP accounts into Dovecot?
I've got a scenario where I need to retain a live backup of over a dozen email accounts and within the next several months these accounts will need to be migrated over to a Dovecot.
I became curious ...
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Relay access denied (454)
I have trouble with postfix sending e-mails to any destination (Relay access denied)
And yes, I googled a lot, tried a bunch of things but with no luck. Here is the thing:
I am trying to use Mailman3 ...
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Getting IP suitable for email server
I am trying to use a VPS to host an email server using postfix. OpenDKIM and certbot was used to get DomainKeys and TLS. The data center setup reverse DNS. In case it matters, the IP is 188.68.231.119....
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Postfix Forwarding to two different Mail Servers
I have a scenario where a Mail Server A.example.com has to forward all emails received on @xyz.com to be forwarded to B.example.com and C.example.com.
What is the appropriate Postfix configuration for ...
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Proxmox Mail Gateway - Relay access denied from Unknown Address
Today I found a strange looking traffic in the Tracking Center
Should I be alarmed by this or is this normal? to me it seems very strange.
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Custom error in Postfixadmin
can you please help me to add a custom error to Postfixadmin. In the config.local.php file I add the following to $CONF['password_validation'] = array()
'/([-#*.!@$%^&(){}:;<>,.?~_+=|].*){1}/...
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Postfix change every mail subject before send and receive
I have a standart postfix setup, requirement is that, every mail come and go through my server, must be marked with some random guid (to be used as ticket number later in other systems), mark means if ...
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Estimate amount of emails handled by Exim
I have two mail servers that use Exim, one is dedicated to receiving mail and the other is dedicated to sending mail.
How can I count how many emails a server sent in a month and how many emails were ...
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Ubuntu PostFix smtp.gmail.com Connection timed out / Network is unreachable
So, i have a postfix mail server set up, and when i run the following command:
telnet smtp.gmail.com 25
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Trying 142.250.147.108...
Trying 2a00:1450:4025:c01::6d...
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Mask mail server IP with Postfix header anonymization?
I'm attempting to setup header anonymization on my mail server, running Postfix and Dovecot on Debian.
I've setup some regular expressions to prevent certain meta data, like a client’s IP address, ...
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postfix mail to relayhost gets bounced dsn=5.0.0: how to debug?
Postfix sends mail to relayhost, but relayhost bounces back with dsn=5.0.0 and no further details.
Q: How can I debug this in detail so that I can find out where I made the mistake?
Setup:
smtp-client....
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Nginx mail proxy: tls between the proxy and the server?
When using the Nginx Mail Proxy feature to realize an SMTP proxy, there are several options available to configure (start)tls between the client and the proxy.
However, it appears between the proxy ...
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status=deferred when sending a mail with Postfix on my VPS
I come here after having searched on the net and groped for long.
I got a VPS on Debian 11 with the domain name leibnizproject.com and I want to send mails from it, with the command mail -s "test&...
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Postfix - redirect AND change the To: header
I want to redirect messages with postfix if they are sent from a specific sender. The redirect should be visible in the To: field. For the redirect I tried to use this header_checks rule:
/^From:.*...
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docker project for Proxmox Mail Gateway alternative
I've been using proxmox mail gateway for incoming and outgoing email, is there alternative for mail gateway/antispam but can deployed using docker?
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How to export on a text file the content of all mails in queue?
I'm noticing an anomalous activity for postfix and I want to check the outgoing mails
mailq shows a bunch of mails in queue with their id without any info on their specific body content to give me a ...
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Dynamically move mails into matching mailboxes with sieve fileinto regex
I'm trying to create a sieve script, which files mails into mailboxes (or sub-directories of the inbox) matching a certain subject identifier.
For example if the subject includes 123 (three digits, 0-...
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Dovecot: Disconnected, connection closed, auth failed
I’ve installed Postfix+Dovecot on my Ubuntu Server 22.04 (VMware Workstation 16 virtual machine). Then I’ve deployed the Ubuntu 22.04 Desktop and started to create a new mailbox in Geary. But it said “...
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DMARC rua unable to send reports via sendmail to local e-mail address?
I've setup a small mail server with Postfix, Dovecot, and MySQL (MariaDB) on Debian. I've also configured TLS with Let's Encrypt. rDNS, DMARC, DKIM, SPF and Fail2Ban are also setup and confirmed to ...
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DKIM and sending email on behalf of many domains - explain it to me like I'm a dummy
We run a server that provides a service for a few hundred customers, and there's a feature that allows them to generate some automated emails which go out to various colleagues and external partners. ...
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Email proxy architecture
I'm trying to figure out how email proxies generally work. I want to present the way I see the architecture, would be glad if anyone could explain which of my assumptions is flawed and what am I ...
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Postfix: "relay access denied" for all incoming mail?
I'm attempting to setup a small mail server with Postfix, Dovecot, and MySQL (MariaDB) on Debian. I've also configured SSL with Let's Encrypt.
So far I haven't setup rDNS, DKIM, DMARC, SPF, etc. - ...
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Postfix bounce email when a recipient is not correctly written
I have an issue with a postfix install, version 3.5.17, in a email server with Debian 11, where when given an email with a list a recipients and if a recipient is not well written, like using ...
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Root domain in SPF record instead of full hostname
Can i use root domain like google.com instead of _spf.google.com in SPF record?.
My SPF record
v=spf1 include:_spf.mx.cloudflare.net include:_spf.google.com include:mxsmtp.sendpulse.com +a +mx ~all
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SPF Limits and SPF Merging
I am using Zoho Mail, AWS SES, GMAIL SMTP, Cloudflare email route and Yahoo SMTP. they all have there own SPF record. i saw on Google the only 1 SPF should be added in hostname and maximum 10 SPF ...
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Generate DKIM for Gmail Free Account
I am using Gmail SMTP with wordpress to send mail with my custom domain (user@example.com). Emails are successfully sent but always land in spam folder in every webmail provider (Eg, Gmail, Rediffmail,...
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Postfix: outgoing email error
Email send but not reached the receiver's mailbox, mainly for Google, Microsoft, and yahoo.
Already checked blocklisted or not, but no blocked there.
mail queue is mentioned below.
C6A02490A1 11809 ...
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Email failure delivery
I already know the answer to my question, but I need to point to a reputable source to back up my claim, so I'm asking you to please describe what you think about the situation in simple terms.
My ...
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Multiple mail server from different provider for one domain is possible?
I have searched in google before asking here. I got a mixed answer in google.
Can i have a multiple MX record from different mail providers?
Example,
Zoho Mail
user1@example.com
user2@example.com
...
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