SMTP is the Simple Mail Transfer Protocol, the most recent standard of which is defined in RFC 5321. It's the Internet standard for sending and receiving email.

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Setting the IP address that the SMTP service uses in Windows Server 2008

My ASP.NET application running in IIS7 on Windows Server 2008 needs to send email. I added the SMTP feature to Windows Server 2008. The problem is that my server has multiple IP addresses and I ...
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How do I set up SMTP on Windows Server 2003 to forward all emails to a given address?

I'm setting up an internal SMTP server to handle software tests which involve the sending of emails. I want to configure the server so that any emails sent to myinternaldoamin.com get relayed (is ...
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Install SMTP Service on Windows 2003 SP2 without Installation CD?

I need to modify my development environment, a virtual image using Windows 2003 SP2, to install the SMTP service under IIS (6.0). The virtual image is a corporate build, and I do not have access to ...
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Block mails with local from-addresses from unauthenticated senders using courier-esmtpd

We run a small courier mail server (courier-esmtpd). It is configured to accept mail from authenticated clients without recipient restrictions and mail from everywhere to local addresses: ...
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Under what circumstances (if any) should an MX record point to localhost?

I'm thinking that there's absolutely no reason or justification for this, but before I open my mouth and get some admin in deep kimchi, I thought I should ask. Is there any circumstance in which an ...
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What to do if one doesn't want to receive email bounces?

Background—the standards RFC 5321 §4.5.5 states: All other types of messages (i.e., any message which is not required by a Standards-Track RFC to have a null reverse-path) SHOULD be sent with ...
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554 5.7.1 <mail_addr>: Relay access denied centos postfix

I have problem in send mail from postfix in centos I have following setup mail server postfix for sending mail but I am getting error. As in the link I tried following commands telnet localhost ...
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Postfix relay host connection fails: timed out while receiving initial server greeting

I have an Elastix server box that I want to send email notifications of voice mails from. I'd like to send them through our company email (hosted by shared web host provider Bluehost). I have followed ...
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How to set exim4 to send email anywhere but only from authorised users?

Struggling to get my head around the various relaying controls in the exim4 config. I can send email from my server, I can send email from home and work (because I explicitly added suitable netblocks ...
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Logwatch is not respecting MailFrom

I've gone through today to setup Logwatch on my server and have installed this all successfully. I've followed this guide on Digital Ocean and set the MailFrom parameter to: MailFrom = ...
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GitLab not sending mails

I have a Linux Ubuntu 14.04 installed on my VM. Recently I have installed GitLab 7.8.2 using the instructions on GitLab site, and encountered problems in making Gitlab to send mails. for example, ...
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Postfix + Php Mail() VS Postfix + SMTP

Most CMS (Joomla for example) comes with php mail() as default and has the option of changing it to SMTP if we want. I will be setting up both the webserver and mail server (Postfix) in the same VPS ...
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Flood of traffic on port 25

I am getting thousands of hits on port 25, over 400,000 connections in a day. I am using sendmail default settings on Debian 7. Mailserver is not configured. Please see below Nginx access logs ...
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1answer
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Preventing email blasts with Exchange 2010 IP Throttling (or any other technology)

We need to slow down the rate email spam is sent through the Exchange system from our developers' buggy applications. How can I throttle email messages in Exchange 2010 by Source IP, or sender, so ...
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2answers
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Can't get SmarterMail to work on fresh Windows 2008 server

Really having trouble with this, I've been through all the guides I can find and get stuck, using latest version of Smartermail 8 on Windows 2008 with IIS7.5. I have it setup so I can SEND emails ...
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1answer
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Postfix + SASL = “Relay Access Denied” when sending from outside the network

I have in /etc/postfix/main.cf: smtpd_sasl_auth_enable = yes smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_unauth_destination and SASL seems to be working: $ ...
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SMTP service detection

I have some basic questions regarding SMTP connections, particularly for Postfix but would appreciate advice for MS Exchange too: When a single relay for a given remote domain becomes unavailable, ...
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reason: 403 4.7.0 TLS handshake failed

Sending email to one particular domain, I get the following error: ----- The following addresses had permanent fatal errors ----- <> (reason: 403 4.7.0 TLS handshake failed.) ----- ...
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cannot find postfix/mailx email in maildir, why not?

In a CentOS 7 development machine, I have configured postfix to allow emails to be traded between localhost addresses. Mailx is also installed. I am able to send email, and the log files indicate ...
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887 views

sendmail foward local mail to relay host

I have read up a lot on the subject but sadly cant get it to work. I have a Centos 6.3 with sendmail installed. The box gets used as a BackupPC server and maybe a samba server later. I want to ...
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1answer
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apache sendmail: trying to change user “from” address from apache to domain account

I apologize if I am asking a question already answered, but my problem isn't really that I haven't found an answer. I have, in fact, found a half-dozen different "solutions" to my problem, tried them ...
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setting up an email server [closed]

i'm about to stop using gmail apps premium and i'm looking at using hmailserver and either zimbra or roundcube as the front end. My question is this: does hmailserver fit well with zimbra or ...
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How to change default sendmail SMTP error codes, responses, and/or DSN text?

CentOS 5.x - SendMail Hi Guys, I'm curious -- is there any way to customize the STMP error codes, response text, and/or DSN body text in sendmail? If so, where is this stored? Thanks, Mike
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Cisco ASA rewriting SMTP traffic to prevent mail sending

We have a Cisco ASA 5505 (version 8.0(4)) that is preventing outbound SMTP traffic; testing with telnet shows connections on port 25 are having everything converted to *s while the same does not ...
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550 Invalid HELO/EHLO must contain a FQDN or IPv6

I've got a Windows Server 2008 box where I host a number of websites (on different domains) that send email as part of their functionality. I've been checking up on the SMTP events and found a number ...
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Why does my server hostname appear in Exim email headers sent from a different domain?

I've had several problems with SMTP emails from my server and domain sent using Exim being blocked by certain other domains, which may have been partly due to certain server settings tripping up ...
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No control panel equivalent of exim /etc/mailips file for configuring IPs for each domain's outgoing mail?

I have a problem with outgoing SMTP mail being sent with the wrong IP address. I use exim for outgoing mail. I found a guide "How to manually configure Exim's outgoing IP addresses", which suggests ...
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208 views

Setup Postfix with SMTP-AUTH over SASL2 with SASLDB for users to send emails

Hello, I spent the last few days trying to setup Postfix with SASLDB to send emails from my application over SMTP on Ubuntu Server 15.04. I searched, read and tested a lot about it but I can't get it ...
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How to unassign self-signed cert from SMTP on Exchange 2010?

We have a GoDaddy wildcard certificate that we have installed into Exchange 2010 and is successfully used on IIS connections for OWA. We have assigned this certificate to the SMTP Service as well as ...
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SMTP Reverse DNS Mismatch Reverse DNS does not match SMTP Banner

I wonder if you could help me? I have set rDNS to mail.simplyislam.biz for IP 178.32.48.104 with my hosting server and also in DNS control panel. However, I am still failing this test: ...
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Dual delivery Google Apps and Postifx (server reject mail from my domain on google)

This is the scenario: I have a server with Postfix and some domains, and now, one of this domains want to use Gmail Google Apps only in a couple of accounts. The end-user configure the domain with ...
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Configuring SPF, DKIM, Reverse DNS for VPS sending email through Google Apps SMTP servers

Today we realized that all of our emails being sent to email addresses of the type <username>@corporatedomain.com were getting rejected. I don't know who is hosting the email for ...
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Set up a Postfix server on Ubuntu for use with Apple Mail (or any mail client)

I set up a Postfix server on my Ubuntu VPS and it works for sending email from the mail utility in the command line. I set up SPF records, DKIM, pretty much everything I could read about. However, I'd ...
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Spam mail through SMTP and user spoofing [closed]

I have noticed that it's possible to telnet into a mailserver that I own and send spoofed messages to other clients. This only works for the domain that the mail server is regarding; I cannot do it ...
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SMTP server force outbound traffic

I'm having some trouble with setting up a SMTP server on a windows server 2003 machine, while trying to send emails using PHP through the internet, but to domain email addresses. Common info: ...
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Postfix - Block email from non-existent local addresses

My question is very similar to this one, but for postfix. We keep getting emails from addresses like "accounting@example.com" delivered to our actual "@example.com" addresses. From my google ...
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Does SendMail Support Outbound TLS Encryption WITHOUT additions to the sendmail.mc file?

CentOS 5.x Does SendMail support opportunistic TLS "out of the box"? I'm used to having to explicitly add the following blurb to /etc/mail/sendmail.mc define(`confAUTH_MECHANISMS’, `LOGIN ...
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How many emails per second is too fast?

I have a growing online business and a dedicated server that I use to send out the occasional newsletter. As it grows past a few thousand customers, I wonder how I can send emails faster without being ...
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Postfix mail size counting

If I'm right Postfix counts mail size with an attachment sent to multiple receivers as one big e-mail. Eg.: User sends mail with 8 MB attachment to two receivers. Postfix thinks it's 2 x 8 MB = 16 MB ...
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SMTP unroutable address

I have set up gmail google app accounts for our own domain, domain.com, so that email is handled by gmail. I.e. MX records point to google servers, A records to our own server IP. This works fine. ...
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What should be the spf record for my domain?

I have my own registered domain. I have a dedicated IP for my domain. I use a shared hosting service for my website. I want to send mail with php's function mail();. I have created one email ...
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What does SMTP 'designate' term mean?

I received a gmail from the address of a friend who is long out of contact. It is possible to use a utility/service such as mail2web.com to define a sender email that differs from the true sender ...
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775 views

Exim managing bounced and failed messages

What is the best way to handle bounces and immediate failures with Exim? An email sent to a large mailing list will generate a large number of immediate failures as well as bounces. I'd like to ...
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648 views

What SMTP port threats to protect against?

I'm planning on creating a simple SMTP Server to auto parse incoming emails to integrate into an application. I chose this method over polling a pop3 account so that I can get instant notification. ...
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935 views

iptables only allow smtp connections with start tls

Is it somehow possible to block/abort unencrypted smtp connections with iptables? effectively rejecting all connections which dont do a start tls.
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Posfix smtpd_sasl_path seems does not work for me

I have such configuration: /etc/postfix/main.cf smtpd_sasl_type = cyrus smtpd_sasl_auth_enable = yes smtpd_sasl_path = /usr/lib/sasl2/smtpd /usr/lib/sasl2/smtpd.conf pwcheck_method: auxprop ...
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SMTP server requirements

Could someone help answer a few questions regarding the networking / DNS requirements for an SMTP server? Assume the server is setup already. Is a MX record required for SMTP? TCP port 25 open to the ...
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SMTP for multiple domains on virtual interfaces

The setup is like this (Ubuntu 9.10): eth0: 1.1.1.1 name.isp.com eth0:0 2.2.2.2 example2.com eth0:1 3.3.3.3 example3.com example2.com and example3.com are web apps which need to send ...
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How to distribute email's delivery between 2 or more servers

We provide Email Marketing service through our online App. We have about 30 customers. And each one has it's own mailling list (5k to 20k emails each). What we really want is to distribute email's ...
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Can I receive mail at another port like 465 instead of default 25 on my mail server?

My Zimbra mail server, which uses Postfix, is working fine. I am able to receive mail at 25 from Yahoo, Hotmail etc., but if I block my 25 port for incoming then mail will stop to come into my mail ...