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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Exim on Centos - Configuring gmail smtp

I want to set up Exim to send the mails through my gmail (actually my domains google apps). I have added the router, transport and authenticator. Specifically: gmail_route: driver = manualroute ...
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2answers
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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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3answers
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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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1answer
160 views

What does “domain or user is in the queue only list. Message queued” mean?

Emails to my domain are periodically being delayed. I see in Exim's log file /var/log/exim_mainlog messages like the following: 2013-05-16 18:58:18 1Ud77q-0002ns-Rd <= email@my.host.name ...
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1answer
461 views

Bash Script To Simulate SMTP Mail Receipt

How would I create a Bash script that simulates SMTP mail receipt and then drops the result into a Maildir-formatted directory (so that Evolution mail reader could read it)? I just thought it would ...
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3answers
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How to force Windows Server 2008 R2's SMTP server to generate NDRs for non-existing local users?

I have a Windows Server 2008 R2 server with the SMTP service enabled, which provides mail relay to another server for some applications. Sometimes, a message comes in with a wrong "To:" address, ...
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1answer
10k views

SMTP server not sending out any emails

I've installed SMTP service on Windows Server 2008. I'm attempting to send emails, however none get delivered. I've scoured logs for a long time, and have solved a few errors. Currently all emails ...
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1answer
916 views

Can I configure Exim to log a given header of all emails sent?

I maintain a custom built web application. Any time this application sends an email, it adds a custom header X-UUID to the mail, to assist me in tracking abuse and email delivery. This UUID is written ...
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1answer
3k views

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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1answer
1k views

What usually happens to a message when server returns SMTP Error 550?

What usually happens when a message recipient can not be found? Will it be deleted or archived on the (destination) server? In 550 case, will the message body be sent at all? Action: failed Status: ...
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1answer
185 views

Microsoft Hosted Exchange: Possible to outsource single mail account?

I have a customer who polls e-mail for a number of accounts in domain example.com via POP. Now they have a VIP user boss@example.com who wants to use Microsoft Hosted Exchange on his mobile phone. ...
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1answer
4k views

How to change sendmail fallback behavior if TLS handshake fails?

I have a CentOS 5.x server running sendmail that is failing to negotiate TLS with SOME various recipient servers. I'm looking into it. In the meantime though, I've noticed that sendmail will NOT ...
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1answer
258 views

Redirect smtp, imap and pop to ssl

I want my users to stop accessing user accounts like IMAP, SMTP and POP without SSL. I can easily disable non-SSL access, but then everything would break. Is there a way to automatically redirect ...
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1answer
2k views

Help me understand Exchange and mail routing

The organization responsible for our mail infrastructure has recently embarked upon a migration to Microsoft Exchange. The group I work with has encountered some problems with the Exchange ...
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1answer
3k views

iptables not letting SMTP through

I am trying to set up iptables to allow SMTP connections, and it does not seem to be working. Here is the output of iptables -L: Chain INPUT (policy ACCEPT) target prot opt source ...
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1answer
941 views

qmail responds 502 unimplemented on STARTTLS

I am trying to send mail with php using the PEAR Mail_queue package. It should be working, and it appeared to work twice, but for some reason I keep getting the following error response from qmail: ...
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1answer
1k views

Sending Email via MS SMTP Server Fails Because FQDN set to Server Name

Some emails sent from our SMTP Server (Windows 2008 running IIS6 SMTP) have begun failing with some of the following errors: Action: failed Status: 5.5.2 Diagnostic-Code: smtp;504 5.5.2 ...
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4answers
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Exchange bouncing email sent by Outlook

We are trying to move users off Exchange 2007. Following various guides online, we've changed our Accepted Domain to be "internal relay" and created a "Send connector" to relay unhandled email for our ...
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2answers
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Exchange 2003 SP2/2007: Address space ignored in SMTP Connector

MS and Postini (Google) are in a tizzy, and long story short, Microsoft was/has blocked Postini's IP block. I think it's been lifted again, but my workaround isn't working (see below). I have a ...
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2answers
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How can I configure the IIS SMTP service to store *all* emails (regardless of domain) in the drop folder?

How can I configure the IIS SMTP service to store all emails (regardless of domain) in the drop folder? I'm trying to catch all emails sent to an SMTP server during testing. I don't want to relay the ...
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8answers
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What are the possible causes of this error: “Unable to > connect to ssl://smtp.gmail.com:465”? [closed]

I'm getting this error on my local machine when sending emails using (gmail's smtp + PHPMailer + CodeIgniter), which I wasn't getting on our previous office (we had to move offices). Severity: ...
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1answer
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Yahoo Domain Keys setup, getting dkim=permerror (no key)

I'm working on getting DKIM installed on my outgoing mail server, to help my email deliverability to my Yahoo clients (all legit emails, etc, no spamming). I've got DKIM-Signature: and ...
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1answer
49 views

Postfix: Fall back on SMTP relay that has internet access

I have a scenario where I have: Postfix server M (Stores mail) Postfix Server A (Relays mail using internet connection IA) Postfix Server B (Relays mail using internet connection IB) Internal DNS ...
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1answer
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Routing SMTP Connections to Different IP Sets with IPTables

I'm trying to set up two different IPs for SMTP that each get routed to two different sets of IPs, with no IPs shared between the two sets. I'm trying this, but it mixes the two sets of IPs so that ...
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1answer
3k views

Postfix client host rejected

I set up Postfix+Courier+Roundcube on Ubuntu 12.04, but when I try to send an email with Roundcube, I receive the following error: /var/log/mail.log : Dec 30 20:54:35 server postfix/smtpd[31465]: ...
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1answer
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Cannot send email from EC2 instance on port 587

I have written a mail service for our flask application that uses Celery and RabbitMQ to send emails (using gmail). I have got the celery consumer and producer communicating okay but I cannot get to ...
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2answers
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Sent items via Exchange SMTP stored in the users mailbox

Using Exchange 2010 server, is there a way to store outgoing emails in the mailbox's sent items folder when an SMTP authenticated user is sending an email via the exchange server's SMTP server? (I.e ...
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2answers
2k views

Postfix smtp server works from localhost but not from afar

I'm trying to set up a smtp server on my domain (wixencafe.net), and i'm using postfix for that. First thing is, postfix delivers emails coming from outside, that is, if i send an email from ...
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1answer
83 views

What is the benefit of using DKIM to sign Content Type?

DKIM has the ability to sign headers on a per-header basis. I looked at Google's headers, and they DKIM sign ContentType. What is the security benefit of signing ContentType?
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1answer
216 views

Exchange 2007 Transport rule only works on SMTP

We've setup a transport rule to catch mail sent to people that have left the company. We've then created Exchange contacts for the mailboxes that were closed and so we can refer to them from the rule ...
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1answer
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Can't make Dovecot communicate with Postfix using SASL (warning: SASL: Connect to private/auth failed: No such file or directory)

Solved. I will leave this as a reference to other people, as I have seen this error reported often enough on line. I had to change the path smtpd_sasl_path = private/auth in my ...
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2answers
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Database mail won't send emails

I am trying to setup database mail in ms sql 2005. I setup but everytime I try to send a msg through their email tester it fails and I get this msg. Date 7/7/2010 10:54:12 AM Log ...
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6answers
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Dummy SMTP server as a service

I have a Windows Server 2008 machine with IIS installed which is hosting a webapp that is sending some notification mails once-in-a-while. What I'd like to do is to monitor the email sent by the ...
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3answers
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Sendmail relay out of Amazon EC2?

I have a site running on CentOS 5.4 through Amazon EC2. Unfortunately, Amazon has had nothing but trouble with their entire IP range getting black listed from spam tracking services regularly. I need ...
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1answer
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IIS6 SMTP and TLS on outbound connections

In the options for setting up the SMTP server hosted in IIS, there exists an option to enable TLS on outbound connections which I want. However I also want it to be able to fallback to clear text in ...
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1answer
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Configure Domino to use SMTP routing and hMailServer

I have been trying for a couple of days to set up a Domino 8.5 server. Basically, I want everything to be run inside a local network. Right now I can send email to other user in the Domino directory ...
3
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1answer
461 views

What PID is making outbound connections on port 25?

What is the most ready way to log the PID and process name of anything making an outbound connection on port 25? This is on a 2008 x32 server without the windows firewall enabled. I'm ...
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0answers
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nginx as smtp proxy [closed]

I was ordered to configure nginx as SMTP proxy. That's all details I have. I've looked though some books and docs and don't see neither any examples of such configuration nor explanations of why this ...
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3answers
231 views

Mail relays or SMTP services for use in code

I'm looking to start using an SMTP or mail relay service. I've found quite a few out there, but I'm not sure if there are advantages to one vs another. The only requirements I have are: can send ...
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1answer
221 views

Is Sender Policy Framework (SPF) effective in preventing Phishing emails?

As defined in RFC4408, Sender Policy Framework only checks the envelope sender (aka MAIL FROM). The From: header is not being tested. As it is the value of the From: header which is usually displayed ...
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6answers
387 views

How to centralize my mail?

I get a bunch of mail on about 20 different servers that I'd like to get to one. The boxes are running Linux and right now my solution is to create a TCP relay. I want anytime traffic coming in on ...
2
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3answers
978 views

SMTP session between 2 mail servers on the internet: Without authentication?

I have some basic question about SMTP (try not to laugh too much). When i try to use SMTP via telnet to send email on google it requires authentication. Mail servers use SMTP to relay messages ...
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2answers
431 views

How do I log tls-encrypted smtp traffic?

I'd like to know what my local postfix says to the Amazon SES smtpd after the STARTTLS. In plain text, so I can understand it. Amazon SES requires TLS, so I can't temporarily turn it off. I currently ...
2
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4answers
739 views

A flexible SMTP server that's open source or free [closed]

We currently have our own in-house email marketing software for our newsletters, and were using SQL server's SMTP agent to send emails through our local SMTP server (IIS) and then onto our ISP's SMTP ...
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3answers
1k views

Postfix or exim: Automated/Programmatic and forwarded email setup

I'm looking to replace our current use of an external smtp provider with an in-house installation. It should handle the following situations: Certain addresses should be forwarded to gmail ...
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3answers
96 views

In a linux-based email server, how can one prohibit SMTP/IMAP/POP connections from clients while still using Webmail (Roundcube)?

With a fully functioning linux-based email server (running postfix/Dovecot) how can one disable the ability to connect to SMTP/POP3/IMAP with external mail clients (or telnet, etc) while still (and ...
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6answers
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Does disallowing sending emails via a SMTP server that doesn´t have the same address help preventing spam or is it dangerous?

I am working in a small programming company and administrated the mail-servers for quite a while. Now we moved our web site and the MTA to a company that we considered to be more professional. But I ...
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2answers
64 views

Postfix seems to send spam

I recently discovered this in my postfix-log: Aug 4 11:09:12 mail postfix/smtpd[71597]: connect from unknown[59.88.35.206] Aug 4 11:09:14 mail postfix/smtpd[71597]: Anonymous TLS connection ...
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3answers
1k views

postfix fails to send mail with “fatal: unknown service: smtp/tcp”

I have installed postfix, and when I tried to send a mail to gmail it told me that it has been sent, but when I checked my inbox in Gmail I didn't saw it. This is how the connection looked like: $ ...
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3answers
203 views

What is the sendEmail equivalent on CentOS 7?

I am trying to follow the steps below. But there is no sendEmail on CentOS 7. I have looked at a few alternatives like Postfix, but I am not sure of the script commands. Alternatively you can use ...