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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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mail not working pointing at old server

Hoping you can help, I'll preface to say that I'm working for a small company and I'm the "IT Guy" as I'm not sure what to ask google, and I've searched here for hours, and still no closer to an ...
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0answers
16 views

High-level requirements for starting construction of email server from scratch [on hold]

I would like to know how to deploy something like SendGrid to Google Cloud. That is, I don't want to use SendGrid, I want to build something like SendGrid. I saw How to setup a mailserver on Google ...
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0answers
29 views

Google rejects all of my emails [duplicate]

recently I moved to a new Cpanel server and I'm facing a big issue when I send emails to Gmail accounts, the system showed an error message ECDHE-RSA-AES128-GCM-SHA256:128 CV=yes: SMTP error from ...
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19 views

postfix sender dependent relay and transport rules

in our system our exchange server can not do "sender based mail routing" so it sends all emails to a (redundant) linux system which should do sender based routing and also it does IP randomization in ...
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1answer
36 views

Postfix receives email but doesn't send [new to server management]

As the title suggest, I'm struggling to get the mail server to send emails. I recently purchased a VPS for hosting and I'm currently trying to set up the mail server which can now receive emails but ...
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20 views

postfix: keeps appending domain name to sender

I've got two servers with the same setup. The first sends mails fine, the other one will not send mail. It appears the problem is the sender. When I send a local mail using: echo 'Message' | mailx -s ...
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26 views

postfix email not receiving from yahoo.com, or google.com, but it will receive from my other domains

I set up Postfix on my server with the goal of receiving email for "mydomain.com" and then piping the email to a php script for processing. I'm not receiving email from yahoo or google, but I am for ...
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0answers
17 views

How to configure postfix SMTP server to send mails from an application [closed]

I have a working postfix SMTP server, I need to configure it to my application. I have a java application which sends emails to my customers. Currently, I'm using SendGrid(SMTP provider). As I have my ...
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30 views

Cannot send e-mail to postfix mail server

I have a Wordpress server (on Ubuntu 16.04.02) on which I'm trying to set up a personal e-mail server using Postfix and Dovecot. I have followed this tutorial, and now I'm at the point where I'll try ...
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1answer
30 views

How can I set up a local mail server and forward external email to another? [closed]

I would like to set up an email server, using Redhat 7.6, let's call it mail.domain.tld. The box is realm-joined to that domain. I want to create email addresses for domain users, for example fred@...
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34 views

PowerMTA routing loop detected

I am facing with an issue, I have spent a day trying to solve it. Everything works fine except sending mail between mailboxes of the same domain configured as a virtualhost. Here is my configuration ...
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0answers
35 views

Resolve SPF config for Google to send mails [duplicate]

After switching hosts, I am currently unable to autoforward email using Gsuite under our domain address we did previously. When checking Gsuite toolbox, I received this error: "SPF must allow ...
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1answer
28 views

doveadm backup doesn't transfer mail from root INBOX

I'm trying to migrate IMAP mails from dovecot 1.1.20apple0.5 (osx) to dovecot 2.2.33.2 (ubuntu). I'm using "doveadm backup" to migrate my data. It works fine for all subfolders, but the root INBOX ...
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0answers
41 views

SMTP recipient's server gives 5.0.0 Service unavailable for some messages but not for others [missing SRS?]

I run a CentOS 7 sendmail SMTP server. For some addresses (a@myclient.com), a virtusertable entry causes my server to forward messages addressed to that address to the client's ISP (charter.net) or ...
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1answer
29 views

550 5.7.501 Service unavailable, Client host blocked using Spamhaus

I have a mail relay server with postfix configured in the company that I work and we are doing a new Virtual Machine with a new mail relay server because we are changing to another network. The ...
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2answers
29 views

Error performing TLS handshake with Dovecot 2.3 upgrade

I was getting the error message "Error performing TLS handshake: An unexpected TLS packet was received." in my email client after Dovecot was upgraded from dovecot-2.2 to dovecot-2.3. No email was ...
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1answer
23 views

Postfix using backwards-compatible (SSL/TLS only Mailserver)

I run a SSL/TLS mail server with Postfix and Dovecot over SMTPS (465) and IMAPS (993). Unencrypted connections do not work and there is no fallback. Every time I restart Postfix I get the message "...
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2answers
58 views

Back up Rspamd Spam/Ham databases

I use Rspamd to filter my emails from spam. The spam filter has already been trained with more than 300.000 emails. Is there a way to save this "knowledge" or transfer it to another system?
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19 views

cant send an email to host mailserver via postfix

so i have a host myhost.com that have a sub domain b2b.myhost.com . in myhost.com i have some mail accounts like info@myhost.com and support@myhost.com and the sub domain is routed from my server that ...
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1answer
24 views

Alias to forward mail to all addresses for a domain using Exim

I'm using Exim v4.91 in a CentOS 7 server hosting more than one domain and I'd like to set up a group address/alias to forward mail messages to all addresses of a given domain (one for every domain). ...
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1answer
43 views

Whats the purpose of getting daily DMARC reports from google about my Mail Server?

I've been getting DMARC reports from google everyday after setting this up on my domain to prevent domain spoofing. Do I really need to have this daily report? I've never opened the attached zip file ...
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1answer
46 views

Emails still going to Gmail & Hotmail spam after removing host from several blacklists

As I mentioned briefly in the subject the IP address of our mail server got blacklisted a while ago. One of the sites on the server got hacked, which resulted in the addition to a couple of blacklists....
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1answer
34 views

Lotus domino 550 5.1.1 Error: user unknown on a newly created database

Good Morning i'm having some trouble with a newly created Domino Database. When i try to send an email from an external address, i get "550 5.1.1 Error: user unknown" error i've created the database ...
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10 views

Get email delivery status data in Axigen

We have an Axigen mail server, we want to track all email delivery status and save in a database. Is there any API or simple way to access these data?
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1answer
34 views

E-Mail spam from localhost without having an open relay

I use ubuntu with postfix/dovecot for e-mail purpose. Now I have the problem that mails are being sent by unauthorized user, despite the fact that I don't have an open relay. My mail.log contains ...
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2answers
34 views

Relaying mail for a machine with port 25 blocked [closed]

I recently moved and had to start using a new residential ISP (my old one doesn't serve the new address yet). To my dismay, the new ISP has no option of unblocking the TCP/25 port even when you buy a ...
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0answers
32 views

how to filter message in postfix where sender address is same as recipient address

I receive a lot of messages on postfix (80 domains) where sender address is the same as recipient address. these message contain phishing or ask for money pretending to have hacked account. I would ...
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1answer
10 views

Sogo-tool runnng as cron and crashing server but apt says it's not installed

I've got a Ubuntu 16.04 LTS dev server setup and today it crashed. I found the following log entry in syslog right before the crash. Mar 6 05:36:01 SERVERNAME CRON[7172]: (sogo) CMD (/usr/sbin/...
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1answer
27 views

Dkim record fails - A public-key (p=) is required

I setup dkim record using following tutorial. But when I check the mx records using googleapps toolbox and dkimcore cheking tool it gives error google says dkim is not setup, dkimcore says A public-...
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1answer
17 views

exim filter not working on long emails

I was trying to set a file extension based filter in exim. if $message_body contains "pdf.gz" or $message_body contains "pdf.arj" This filter does work on small mail, such as mail with only test ...
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2answers
381 views

domain name system - rDNS is not exist [closed]

I need some help with Reverse DNS as I have got a problem with it. I have setup rDNS on my hosting provider which I use rdns1.example.com and I have a server hostname which it is gateway1.example.com. ...
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1answer
21 views

How to send as a proxy address

I have sort of a weird situation that I need to get solved. We use office 365 (exchange online) for our email server. My company is going through a rebranding. Currently, we have one domain that ...
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1answer
23 views

Is it possible to user based mail send control on Postfix?

i am using postfix - dovecot based mail system and i have my own frontend - backend api structure for send and recieve mails. I am slightly new on postfix and i want to do something like; I have an ...
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1answer
32 views

Mail server - relay with TLS and authentication

I am working with postfix and dovecot and I can't seem to find out anywhere how to create this setup: 1) allow submission of emails from outside (telnet) where the sender domain is the local server ...
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3answers
84 views

Why use DMARC when SPF -all can do the job?

With DMARC I can set the policy to rejct mail. But isn’t it the same I can do with -all from within a SPF? Same goes for quarantine and a softfail ~all. Beside the reporting where is the benefit ...
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ESET Mail Security for Linux as mail gateway/proxy for Synology mail server

It's been a really long time since I've been doing such stuff, but maybe others still do. I have a license for ESET Mail Security that I used for Exchange 2010, but now we're migrating to Synology's ...
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1answer
25 views

Mail cipher - what to use and how many servers are up to date for secure connection? [closed]

I have setup my personal self hosted mail server. I use Postfix, Dovecot and rspamd. My question is about cipher suites, this topic is more discussion that specific answer seeking. I have setup all My ...
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1answer
52 views

Route local outgoing mails to relayhost

TL;DR: I'm trying to force postfix to route mail sent from local user to another local user to be routed to another server (relayhost). This should not apply to incoming mail from external to local. ...
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1answer
40 views

Should I enable port 587 for mail relay access?

I run a virtual email server using Postfix that forwards emails addressed at domain.com to specific Gmail / Hotmail accounts. This same server also acts as a mail relay, and uses saslauthd to allow ...
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0answers
23 views

Set up email server for cron job

So I've been running a cron job on a daily basis and I set it up with the MAILTO variable so that I receive an email with the error output if the command ever fails. It was working fine up until today,...
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3answers
34 views

Sending email to a server that requires a login [closed]

I'm trying to understand how SMTP servers work in production environments. I am wondering how email can be sent from server A to server B if server B requires a login. A real life example of this ...
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1answer
66 views

sendmail aliases - send to root plus external address?

There are plenty of examples of how to use aliases to send email to multiple addresses, but I'm interested in sending to an internal name and an external address. For example, this doesn't work, but ...
1
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1answer
58 views

Is it an issue when I change the IPv4 address of my SMTP server?

I have a postfix/dovecot setup for a personal mail account. It's really just a one-man mail setup. Now I want to move my setup to a new VPS which means it'd get a new IPv4 address. My concern is ...
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1answer
67 views

Postfix: Illegal address from unknown sender

I got this alert from my maillog postfix mail postfix/smtpd[13563]: warning: hostname riservata.miami19.mia.seabone.net does not resolve to address 195.22.199.54: Name or service not known Do you ...
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2answers
65 views

blocking port 25 cause mail server cannot receive mail

I use TLS for my postfix and dovecot,and I ready test centos 7 mail server by various tools,result as below: Priority: 5 Connection established: yes TLS: yes SSL: yes Cipher: TLSv1/SSLv3, Cipher is ...
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1answer
30 views

What happens to sent emails from localhost without internet connection? [closed]

we're building a webshop that will serve as a kiosk on a fair. The fair visitors stop by and order some things at the shop. We'll have some Tablets where the visitors can shop through our kiosk and ...
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1answer
47 views

Abuse report for spamming…abuse report [closed]

Few weeks ago, i activated on my server on automatic abuse report mail when someone try to brute force my SSH, i did it because i got an average of 3000 spamming IP each weeks. But today, my ISP send ...
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2answers
294 views

Is this correct for a SPF record based on our setup?

Our company has a SMTP server that sends mail out on behalf of our customers. So a customer would log into our system, go to a specific section, and can fill out a form to send an Email to whoever ...
2
votes
1answer
200 views

`connect to private/policy-spf: No such file or directory` when receive mail by postfix in centos 7

My system is centos 7 with postfix,dovecot,pypolicyd-spf, opendkim. I can send mail but cannot receive mail, I notice warnings as below: Feb 6 20:01:09 srv-8327 postfix/smtpd[20391]: warning: ...
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0answers
18 views

Malformed DFIM body signature (postfix)

I am having some trouble with my email server. (postfix/dovecot on ubuntu 18.04 LTS) I am getting an invalidated DKIM body signature. This is what I get from the header. DKIM-Signature: v=1; a=rsa-...