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.
3,140 questions
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Setting up DNS for routing mail to corresponding subdomains
I'm trying to configure DNS for handling mail across multiple subdomains, where each subdomain has its own mail server. My goal is to route mail for user@%subdomain%.example.com to the server hosted ...
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Forcing HTML email format with postfix - SMTPD's content_filter option
I'm using altermime with postfix so I can include signatures for each email address with the "-o content_filter" option in /etc/postfix/master.cf for smtpd.
The HTML signature is correctly ...
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Postfix: Delay between individual messages
I need to have a delay between individual messages on my postfix server.
There is a way with default_destination_rate_delay, but there is a minimal value of 1 second.
Is there any way to make it less?
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How to troubleshoot wrong SSL cert for SMTP connection
i have a mailcow mail server, everything works fine including sending and receiving mails. However when i try to setup my account in Thunderbird, it automatically finds the Configuration needed. After ...
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How to Block Outgoing Emails with Forged "From" Headers?
I'm managing a mail server stack using Postfix, Dovecot, SpamAssassin, and Amavis. My primary concern is outgoing emails where authenticated users attempt to set a From address different from their ...
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SES drops connection (to me) at EHLO
Hi all – I’m reaching out to SF with my first question. I’m stumped on an email problem.
I have a contact form hosted at carrd.co, who uses SES to send email. I’m using this to send to a self-hosted ...
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CodeIgniter not sending email through SMTP
I have migrated my CodeIgniter 4 app from a shared hosting to a VPS but now the application is not sending emails, this is the return I am getting when processing the pending mails to be sent:
Unable ...
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Dovecot quotas with users in MySQL
I have the storage set as mdbox. Trying to get quotas to work with the user information stored in the database, right now with a simple table like this:
+----+-----------+-----------------------------+...
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Postfix/Dovecot log: "auth: Warning: auth client 0 disconnected with 1 pending requests: EOF" - how to hide/fix
I've got a Debian mail server and set up error logging mails. I always used to get a lot of emails with the following line:
auth: Warning: auth client 0 disconnected with 1 pending requests: EOF
Maybe ...
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Docker mail server suddenly stopped receiving mails - Sender address rejected: Domain not found
I run a mail server on a small VPS running docker-mail-server.
It was working perfectly fine until 2024-10-02, where it started rejecting email.
I renewed the certificates, even though they expired on ...
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Postfix additional character for + sub-addressing
For many years already our mailservers have supported the plus + character in the local-part of an e-mail address as a separator for sub-addressing & RFC 5233 which allows our users create ...
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Linux MTA for forwarding and/or autoreply only
I am looking for an MTA (running on Linux) to auto-reply and/or forward e-mail based on the e-mail address, and optionally the sender.
At the moment the current MTA (Postfix) is the destination of ...
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Dovecot LMTP Crashing on Large Emails (Sieve Rules Suspected) - Ubuntu 22.04
I noticed errors in the incoming emails on my VPS over the past month, particularly with emails containing large attachments (>10 MB).
This issue seems to affect multiple mail users, resulting in ...
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Postfix cannot access Opendkim Socket
I have a ubuntu 20.04 server and a domain example.com
I installed postfix and opendkim via apt.
In /etc/opendkim.conf I have
Socket local:/run/opendkim/opendkim.sock
The file exists.
$ ls -l /run/...
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smtp server fehler 451 (471 Tempary lookup failer
ich folgendes Problem beim versenden von eMail's bekomme ich folgende Fehlermeldung 451, 471 (Tempary lookup Failer). Woran kann es liegen das keine Mail's versendet werden ?
Rolli von RME
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How to set envelope sender (MAIL FROM) depending on the envelope TO field in postfix?
I am using postfix to manage email on a certain machine.
Some mail eventually gets relayed to a particular address, say [email protected], and the mail server serving this address REQUIRES the ...
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Can't configure systemd:postfix on pacemaker to work properly
Objective: I have a cluster managed by the pacemaker, I want my postfix resource to depend on clamav-daemon.service and mailscanner.service. If either one of these two resources fail, the IP jumps.
I ...
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Email sent from my VPS sometimes go to quarantine [duplicate]
Description
I created a website/app which requires an PIN number to be sent to the user during 2 factor authentication. In addition forgot password needs an email to be sent to the user.
There are 30 ...
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SOGo Login Without Full Email Address in Mailcow Setup
I've set up Mailcow with the SOGo client using Docker Compose. Currently, when logging into SOGo, I need to enter the full email address, for example, [email protected].
However, I'd like to change this ...
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Linux email server configuration: the postfix relay_domains setting and sending email
I am trying to set up an email server on an Arch Linux VPS using postfix and dovecot. I'm using plain unix password authentication, in which dovecot handles SASL authentication for postfix. For the ...
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TLS connection Error from exim4
My mail server, which is operated with myVesta, has a problem when I want to send mails. (Receiving works)
Unfortunately I only get the error from Thunderbird
mailnews.send: Sending failed; The ...
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Roundcube SMTP remote server 465 SSL port no connect
EDITED!
Without SSL, only the server address and port 25 works properly, but i want to use SSL.
Original:
I use an old server for mail service, and i use a new server for webpages.
I installed ...
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Postfix mailserver with two IPs. Map each sending IP to different application
I have one mail server (Debian 12, Postfix) with two public IPv4 IPs for two applications.
I must send all emails from application A from IP 1.2.3.4 and application B from IP 5.6.7.8.
Both application ...
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Postfix relay mails from alias domain to main server
I use my own server as a relay for customers sending newsletters. It's necessary because of the webhoster limitations.
I've added the domains as virtual_alias_domains and a webmaster@ to ...
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Dovecot fails login with [email protected], only direct username works
A login to dovecot only works with the defined username in the /home/ directory.
I've already tried auth_username_format = %n and auth_username_format=%{if;%d;eq;my-fqdn-hostname;%Ln;%Lu}, both with ...
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Configuring an email server with multiple domains
I have a single server where mails are processed, and I'd like to use multiple domains.
For example, if the domains were example.com and example2.com, and I had the following DNS records set up:
mail....
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Can I restrict which users can `sendmail` from an address with Postfix?
I've set up Postfix on my server (let's call it example.com), and I can prevent SMTP clients that don't authenticate as admin from sending email from [email protected] with (for example):
# main.cf
...
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Is there something special about mail.domainXXX.com?
I have been trying to improve an already working DNS configuration for email delivery and found that for some reason I don't understand I need to have a mail.domainxxx.com A entry for my MX ...
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postfix doesnt deliver nor receive mails
I set up a docker container (mailserver/docker-mailserver) on my server.
Postfix is giving me the following log when I try to send or receive a mail:
2024-07-30T17:40:01.753276+02:00 mail postfix/qmgr[...
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Is my Ubuntu/Postfix backup Email server working properly? : "connect to mail.mydomain.com[483.31.59.1]:25: Connection refused" How to fix?
I have two email servers running Ubuntu 22.04, with postfix. My main email server is working flawlessly. However, there are times when the email server goes down for maintanence or updates. During ...
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docker-mail wont send email due to Error: queue file write error
I am using the docker-mail compose setup.
https://github.com/docker-mailserver/docker-mailserver
I get the following error reported to the client " Error: queue file write error. " when ...
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50
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Exim4 with Too Many Connections
In this post I asked what caused the "Too many connections" error in Exim4.
Using smtp_accept_max can indeed help, but it still doesn't help me 100%. Because there could be a DDoS attack and ...
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Why is Gmail labelling DKIM signed mail as spam? [duplicate]
I am running a Postfix with OpenDKIM for DKIM signing.
In the past, I have used a single domain and have not encountered issues with mail being labelled as spam.
I currently have multiple domains on ...
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Why do certificate CNs not match the hostnames provided in MX records?
I'm the author of checkdmarc, an open source CLI tool for checking DMARC and other email security standards. One of those checks involves testing if the mail servers listed in a domain's MX records ...
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Dovecot Mailserver moves mails with "List-Unsubscribe" header to junk, although no spam settings configured
I have my own mailserver setup with postfix and dovecot on an Ubuntu 20 server. The setup is very standard (postfix using mbox files) and has been working nicely for a long time. However, there is an ...
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SMTP Port 25 Issue on Nginx Mail Proxy
I set up an Nginx mail proxy server and configured it to distribute to several mail servers as a front-end server. However, I need to open port 25 in the configuration; otherwise, I cannot receive ...
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Google Workspace / Gmail apparently limiting external recipients to 3000 per hosted domain
I work for an organization whose email, documents, and mailing lists ("groups" in Google parlance) live in Google Workspace, in a Business Plus plan. We have about 120 individual users and a ...
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How can I deliver incoming mail based on recipient domain with Postfix?
I have been digging for an answer to my current problem for several weeks now, so I am asking here in hopes someone can shed some light or point me in the right direction.
I am attempting to configure ...
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Change iRedAdmin roundcube url
Good day,
I am encountering an issue with iRedAdmin. Currently, accessing my webmail requires navigating to mydomain.com/mail. Furthermore, visiting the base domain mydomain.com automatically ...
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SMTP - How to send mail as @example.com when example.com cannot be used as source server/IP
I have run into a bit of an issue when attempting to set up a mail system where the parent domain, example.com, already has A records and a web server as well as many clients utilizing the parent ...
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Postfix and Punycode Domains on CentOS 7 using puny code domain
I'm trying to set up a mail server using CentOS 7, Postfix, Redmail, and Devcom. I'm using a domain with a special character "ø", which I didn't know wasn't normally recognized and is ...
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DKIM Record Externally Readable Yet Emails Not DKIM Signed
I have a VPS and launched my own mail server on it using Postfix & Dovecot.
Emails are now going in and out of my self-hosted mail server.
I created reverse A, SPF, DMARC and DKIM records for ease ...
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Postfix Mail being redirected to private inbox
I am relatively new to Linux, setting up servers and especially handling mail related things. I've bought a new domain and rented a VPS, which now hosts my website. I need a more open environment for ...
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Multiple Postfix Instances *without* postmulti
I have been running multiple instances of certain services (php-fpm, mysqld, httpd) and am now trying to do the same with Postfix.
Searching online, I have so far only been able to find descriptions ...
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postscreen "deep protocol" tests and multiple MX IPs?
In the Postfix postscreen readme, it says the main limitation of "after 220 greeting" tests is that a new client must disconnect after passing these tests. To partially mitigate problems, it ...
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Server certificate has expired
When I try to log in to my mail client I get this:
This certificate belongs to:
mail.ssk.pm
This certificate was issued by:
R3
Let's Encrypt
US
This certificate is valid
from Thu, 21 ...
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How to locally read Maildir archives in Windows?
How can I locally open a read-only Maildir backup archive in Windows in order to browse through e-mails, run keyword searches, filter/sort by date or recipient, extract attachments, display e-mails ...
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My email server IP is blacklisted, how can I resolve it?
The IP of our email server 154.116.254.147 was added to the UCEPROTECTL2 blacklist. The error message we received is as follows:
"I am deeply sorry, but I was not able to deliver your mail to the ...
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how to protect postfix mail from gmail spam [duplicate]
I am experiencing an issue with the BDIX (Local Bangladeshi server) server.
I have set up a mail server on the local BDIX server using postfix with aapanel.
I have configured SPF, DKIM, and DMARC in ...
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209
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How can I mitigate a flood of inbound emails that look legitimate to filters?
I have a mail server - postfix, amavis, dovecot. Currently one of my inboxes is being flooded with random email from all over the globe. It's like someone signed me up to 10,000 newsletters all at ...
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