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.

learn more… | top users | synonyms

3
votes
2answers
5k views

How do I track whether a email was successful among thousands (IIS 6, .NET 3.5)

I want to be able to tell if an email sent to a user is successful or not. I've tried looking at the SMTP logs and there appears to be no way to link server requests with server responses. So if I ...
3
votes
1answer
7k views

Postfix: How to make aliases work for virtual domains?

I'm trying to set up a local mailserver. I run Mac OS X Server 10.6 Snow Leopard, and it uses Postfix as server. I set the server up using the GUI and I'm doing all virtual settings via the terminal. ...
3
votes
1answer
610 views

Changing HELO name in Exchange 2003

When I telnet to my mail server on port 25, I get the following: 220 myownmaiil.com My question is, how do I correct the spelling mistake in the mail? My mail server is Exchange 2003
3
votes
4answers
288 views

Minimize the chance my email is blocked/filtered as spam

I'm running a web-based store where order confirmations are sometimes blocked and don't reach the intended user. The structure of the business model is such that our product is marketed to the ...
3
votes
5answers
20k views

mail loops back to myself | postfix

Hi I have an issue with bounced mail it does not happen all the time but at the same time is very frequent. Most of the time if I send an email to an address that does not exist then i get a bounce ...
3
votes
1answer
322 views

Change Outgoing SMTP port in Exchange 2003 with a slight twist

I feel like I should know this, but its been a long week already. I have a customer with an SBS Exchange server on their LAN. They currently have their MX going to Postini, who is then delivering the ...
3
votes
3answers
1k views

Sendmail : ignore local delivery

I've a Ubuntu webserver with Sendmail as my MTA Currently when i email outside my webserver's domain e.g. example.com to something like gmail or any other email outside the example.com domain it ...
3
votes
6answers
1k views

What is causing email sent from my Google Apps account to bounce?

I have started to get Delivery Status Notification (Failure) messages in response to emails sent from my Google Apps domain account (at offby1.net): Delivery to the following recipient failed ...
3
votes
2answers
444 views

Set up an SMTP server that catches & stores all mail

I need to set up a SMTP server in a dev environment that will accept all mail sent to it (for any domain) and simply store it so we can later see what it has caught. What is the easiest way to set ...
3
votes
2answers
990 views

SPF Setup - Sending from VPS and Google Apps

In follow up to my question here, how on earth do I setup a SPF record?!? I understand that I have to add a TXT record to my DNS entries but what to put in that TXT entry is what's confusing me... I ...
3
votes
7answers
9k views

What are the possible causes of this error: “Unable to > connect to ssl://smtp.gmail.com:465”?

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: ...
3
votes
5answers
7k views

How can I set up sendmail to forward all mail to an external MTA?

We have multiple applications that currently talk SMTP to an external MTA. The emails have arbitrary destination domains (they're emails to be sent to our users), but all from the same internal domain ...
3
votes
2answers
269 views

Intermediate SMTP server (exim), how to handle backscatter?

I have a dedicated Ubuntu Lucid box at a hosting provider that is my backup MX (running exim4 4.71-3ubuntu1.4) for domains that I have configured on an Exchange 2007 server on my LAN. So my Exim ...
3
votes
1answer
770 views

DNSBL listed at zen.spamhaus.org - cant get outgoing mail working? Am I interpreting the response correctly?

I have problem with a mailserver and there is something I kind of not understand! I can connect, authenticate, specify the sender address - but when specifying the reciever i get a error 550 which ...
3
votes
3answers
2k views

How is LinkedIn able to send emails from my email address without getting flagged as spam?

When linkedIn sends and email to you about adding someone to your network, the email appears to come from this person's individual email address (not something@linkedin.com). To me it doesn't seem ...
3
votes
3answers
259 views

Does our IMAP access have to be behind our VPN?

I work for a small company (around 40 people) and our email is available via IMAP - but only when connected to our VPN. For iPhone users (and generally), the VPN connection appears to be an ...
3
votes
1answer
237 views

Force delivery retry without restarting the SMTP Service on Windows Server 2008 R2

I have a Windows Server 2008 R2 box hosting 3 virtual SMTP servers; vSMTP01, vSMTP02 and vSMTP03. The first two are configured to deliver all messages to dedicated smarthosts, while the last is set ...
3
votes
1answer
108 views

empty EHLO from all around the web, is it a bot? [closed]

I've been getting this since a few weeks ago: Transcript of session follows. Out: 220 www.example.com ESMTP In: EHLO Out: 501 Syntax: EHLO hostname In: HELO Out: 501 Syntax: HELO hostname ...
3
votes
1answer
253 views

Is null return path reliable indication of a bounce?

I have a mailbox that receives bounces as well as normal email (the latter includes messages from automated services). I want to filter out the bounces and forward them to another mailbox. Assume I ...
3
votes
1answer
647 views

postfix misconfigured: “mail for (domain) loops back to myself”

I've just installed postfix on my debian system, so I have a default configuration, apart from the following values in /etc/postfix/main.cf: myhostname = mydomain.com alias_maps = hash:/etc/aliases ...
3
votes
2answers
530 views

Can Exchange 2010 Re-Route Outbound Messages Based On X-Header?

I'd like to know if it's possible to configure Exchange 2010 to read x-headers from an outbound message (say, user@internaldomain.com to user@yahoo.com) and then re-direct the message to an alternate ...
3
votes
1answer
3k views

Dovecot - Unable to receive mail - Fatal: Plugin 'sieve' not found

Struggling to Dovecot/Postfix set up on Ubuntu 11.10, Dovecot version: 2.0.13, Postfix version: 2.8.5 I can send outbound mail using the mailx command, but I can neither receive mail or send mail ...
3
votes
1answer
2k views

Turning on UFW stops my e-mail client functioning (both imap and smtp) even though they are allowed?

I am using ubuntu 10.04 on a VPS. Without enabling UFW everythign works fine - imap using port 143. And sends emails using smtp port 587. However, when I turn on UFW a lot of problems are ...
3
votes
2answers
2k views

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 ...
3
votes
1answer
2k views

Exchange 2003 SP2 Mail Delivery Problem - Sending server sends QUIT command to EHLO response

So one of the Exchange 2003 servers I admin seems to be having trouble with sending e-mail to another domain's email server. As per my SMTP log (in NCSA format) this is what I have 66.195.209.243 - ...
3
votes
2answers
281 views

Exchange 2010 Setup

I am testing MS exchange 2010 SP1 for our firm. It's new exchnage installation as we don't have any previous versions. I installed Exchange 2010 with SP1 on Windows server 2008 SP2 (64-bit) with ...
3
votes
3answers
2k views

IIS6 Virtual SMTP server isn't coming back up automatically after a system restart

I've got a virtual server running Win2008 RC2. I've set up IIS6 with a virtual SMTP server on it to be the mail provider for the websites I'm hosting there. It all works great, but if for some reason ...
3
votes
2answers
4k views

How can I configure my postfix server so reject_sender_login_mismatch doesn't block aliases of the main account?

I've recently setup postfix, dovecot, amavis and a suite of other tools using iRedMail, and I'm having difficultly authenticating to my outgoing mail server. The issue is this: xyz@mydomain.com is ...
3
votes
1answer
2k views

How can I configure Exim to drop non-authenticated connections on alternate SMTP port?

I currently only allow connections on port 25 from a mail filtering service's IPs. I have Exim running on an alternate port for SMTP submission. This port needs to allow non-encrypted connections ...
3
votes
1answer
122 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 ...
3
votes
1answer
278 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 ...
3
votes
2answers
1k views

Can't connect to SMTP server

I have trouble connecting to an SMTP server from my PC. I use Debian sid. telnet mail.example.com 25 Trying 12.23.34.45... telnet: Unable to connect to remote host: Connection timed out While from ...
3
votes
3answers
921 views

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, ...
3
votes
1answer
5k 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 ...
3
votes
1answer
526 views

Mail queue retry interval practices

I'm configuring a custom made mail queue. The thing is there can be errors sending mail. Normally, one won't know the reason why the mail didn't reach it's destination. So the most simplistic solution ...
3
votes
1answer
570 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 ...
3
votes
1answer
2k 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 ...
3
votes
1answer
657 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: ...
3
votes
1answer
176 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. ...
3
votes
1answer
162 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 ...
3
votes
1answer
737 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 ...
3
votes
1answer
2k 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 ...
3
votes
1answer
610 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: ...
3
votes
4answers
899 views

How to determine if my mail server is configured correctly?

Does anyone know of an online service (similar to the ones that tell you if a site is up or down) that can connect to a specified mail server and perform checks to see if it is configured correctly? ...
3
votes
2answers
1k views

Simple SMTP server which can redirect all mail to single address?

We're in the process of setting up a continuous-integration server (Hudson running on CentOS5), and some of our unit tests will cause email to be sent. We'd like to configure the server so that all ...
3
votes
2answers
2k views

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 ...
3
votes
8answers
7k views

Emails are being rejected by some email providers

I have this asp.net application that sends out emails. The SMTP server is iis6. The emails are being sent on behalf of our application users and they have different domain names. Most of the email ...
3
votes
1answer
8k views

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 ...
3
votes
1answer
199 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]: ...
3
votes
2answers
1k 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 ...