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

0
votes
1answer
87 views

PTR record not valid for all domains

We have an issue sending emails to certain domains, namely Time Warner and Cox. Last week, we decommissioned our Exchange 2003 server and now our Exchange 2010 server is doing all of the transport for ...
0
votes
1answer
370 views

Configuring external SMTP server on Azure VM - messages staying in queue

I have an external SMTP provider: auth.smtp.1and1.co.uk I am trying to send SQL Server Reporting Services emails via this on an Windows 2012 Azure VM. It is configured sufficiently correctly for ...
0
votes
0answers
169 views

'Cannot get iis pickup directory' in Windows Server 2012

Our system moved from Windows Server 2003(Enterprise SP2) & IIS 6. And new system is Windows Server 2012(Standard) and IIS 6(for smtp mail) & 8. I copied all of web application files and IIS ...
1
vote
1answer
105 views

Email server can send internal, but messages never arrive at external recipients

I'm running MailEnable on my server, and have been for many years. Recently we had an attack on our server, and I was able to close the hole. Since then, our mail server doesn't seem to be sending ...
3
votes
1answer
497 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 ...
0
votes
1answer
325 views

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 ...
0
votes
0answers
100 views

IIS Virtual SMTP Service — Integrated Windows Authentication with Administrator

I'm playing around with the authentication features on an SMTP service running on Windows Server 2008 R2. I have coded up a quick email-sending console app in C#, with support for connecting by Basic ...
0
votes
2answers
208 views

Nagios - NagWin - Send notification with gmail

I would like to send Nagios notifications using my gmail account. I have already set up my hosts I want to monitor and services also. What is the most simple way to accomplish this using NagWin on a ...
-1
votes
2answers
159 views

How is incoming SMTP mail being delivered despite blocked port

I setup a MX mail server, everything works despite port 25 being blocked, I'm stumped as to why I am able to receive email with this setup, and what the consequences might be if I leave it this way. ...
0
votes
1answer
152 views

Postfix: mail going to spam [duplicate]

All emails I send from my new server go to spam in Gmail (and sometimes yahoo). I've never before sent out mass email or spam. What I've already done: Configured reverse DNS Enabled DKIM Verified ...
2
votes
2answers
64 views

How to get feedback from SMTP server, connecting to it from another server in the same network?

I have the following scenario: [HTTP Server]: process messages [SMTP Server]: only send messages [HTTP Server] === connect to ===>>> [SMTP Server] === sends message ===>>> [world] Ok, this is ...
0
votes
0answers
67 views

can't send with postfix but I can whith one user

I have a postfix and dovecot server but when i try to send an email i get an time -out. Im trying to send with the email pinda@treadity.com. A telnet session isn't helping much ether. I get a blank ...
0
votes
1answer
89 views

Exim + Spamassassin, automatically throttle spammy IP addresses

I am watching my email gateway blackhole spam messages using spamassassin - anything over a specific score. Right now, it is dropping around 3 per second. This is great, but I would prefer the spam ...
0
votes
0answers
21 views

email redirection service with reply path through local server

We need to keep a copy of all email conversations on our servers for regulatory compliance. We have contractors that (understandably) want to use their own email accounts We would like to setup a ...
1
vote
1answer
446 views

Can't connect to smtp (postfix, dovecot) after making a change and trying to change it back

I am using postfix and dovecot along with zpanel and I tried enabling SSL and then turned it off as I did not have SSL configured yet and I realized it was a bit stupid at the time. I am using CentOS ...
2
votes
1answer
32 views

Translating return receipts and postmaster messages

I was wondering if it is possible to translate postmaster message (return receipts, notifications, etc), or at least customize them. I ask this because my users (too) often call me in order to know ...
1
vote
2answers
72 views

Email verification with SMTP fails on local machine for certain domains

I want to verify whether mail box exists for a email with SMTP. I am able to do following things : Get MX records from domain Connect to host via SMTP Then I execute following commands : HELO ...
1
vote
1answer
240 views

Sending email with Python/Django through Microsoft Exchange (IMAP)

I have a Django web application which sends email through a standard SMTP, but I want it to use a mailbox from the corporate Exchange server. I would like the emails sent from the application to be ...
0
votes
0answers
129 views

How should I setup outgoing smtp for app emails on load balanced Windows servers

I've recently setup a small group of servers to host a couple dozen asp.net applications that send out emails for things like customer registrations, purchase receipts, error alerts, nightly batch ...
0
votes
1answer
242 views

SPF + ISP Smarthost, always untrusted?

One of the ways mail-servers protect themselves from spam is by SPF-records, a DNS look-up saying what ip-adresses are allowed to send mail from a given domain name. Another way the mail-servers use ...
0
votes
1answer
202 views

False positive rate of CBL

We've come into the office (30+ networked systems) this morning to find that our email server is blacklisted on the CBL for: This IP address is infected with, or is NATting for a machine infected ...
2
votes
1answer
95 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 ...
0
votes
2answers
78 views

unknown receiver “esmtp”

I found this in my log server: sm-mta[11410]: r9BKb6YY021119: to=<woodhzve@ralphlaurensoldes2.com>, ctladdr=<info@188.com> (33/33), delay=2+07:24:18, xdelay=00:00:01, mailer=esmtp, ...
0
votes
0answers
43 views

In SMTP with BINARYMIME format, can “Data” be used instead of “BDAT”

I have an IIS 7 server that is rejecting the following command, however when I use a non IIS server this is accepted. The Error is: 503 5.5.2 Body type BINARYMIME requires BDAT Based on my reading ...
0
votes
1answer
54 views

Configure IIS SMTP server to forward to more than one address

I have the SMTP service installed on Server 2008 R2. Under Domains, if I go to properties, under Route Domain, I have the option to forward all mail to smart host and I currently have one address ...
0
votes
2answers
113 views

Same domain SMTP unauthenticated message relay [closed]

While I was doing some testing on an SMTP server I was able to successfully send mail from knownid@myserver.com to knownid@myserver.com through telnet without any authentication. From a risk ...
0
votes
2answers
293 views

Cant open a port on my linux server [closed]

Here is the thing, my server fails to connect to gmail SMTP with timeout error. I think the 465 port is closed on my server so I did couple of thing, now my csf.config file hase this two lines: ...
-1
votes
1answer
195 views

Can't connect mercury mail smtp server outside local network

I'm using Windows Server 2008 R2, and Xampp with mercury mail. My problem is that I can't send mails via my server outside the server network. My SMTP server is using port 25, which is open and ...
1
vote
0answers
77 views

Configure postfix to limit total number of connections from any and all SMTP clients in a given time period?

I am trying to figure how to configure Postfix to operate within the requirements given by Spamhaus for free usage of their DNSBLs (http://www.spamhaus.org/organization/dnsblusage/). They specify that ...
1
vote
1answer
39 views

What allows a mail server to operate faster or handle more mail? [closed]

I realize that this may be better suited for StackOverflow.com instead, however as I'm not much of a developer, I worry those answers may be way too developer-centric. Although, I would like some ...
0
votes
1answer
232 views

OS X 10.4 Server SMTP Server timeout [duplicate]

I just set up my server today with one of my new static IP addresses to act as a mail and web server. The web server is working fine, and the mail server is working fine to receive mail, but I am ...
0
votes
2answers
394 views

Can I send email unauthenticated to an internal SMTP server which then relays onto authenticated SMTP?

I have a back-end system which only supports sending email to an *UN*authenticated SMTP server, however, ultimately it needs to go via an authenticated SMTP server on the public internet. My idea was ...
2
votes
1answer
3k views

Google SMTP Error: 454 4.7.0 Too many login attempts, please try again later

I discovered that while it was possible to use Gmail/Google Apps as an SMTP server for scripted use, if too many emails were sent I started getting error messages: SMTP Error: 454 4.7.0 Too many ...
1
vote
1answer
426 views

PHPMailer script stopped working with cryptic SMTP error messages

I am trying to send mail in a PHP script via the PHPMailer library. The following code has successfully sent emails in the past without warnings: function mail_attachment($filename, $path, $mailto, ...
0
votes
0answers
44 views

Postfix dosen't forward to Gmail Yahoo Hotmail

I have a problem with my Postfix 2.8.4 (Cent OS 6 with Plesk 11.0) If i sent an email to one of these providers, it will be delivered ok. If I setup my email to forward all emails to one of these ...
0
votes
1answer
50 views

Postfix maillog: warning: host nb-mx-vip1.prodigy.net[207 .115.36.20]:25 greeted me with my own hostname

Mail server on internal system, reachable through a gateway / firewall via forwarded port returned this error. I upgraded my environment (unadvisedly) with Fedora Core 19 and have had lots of ...
0
votes
0answers
97 views

SMTP fails with Status: 5.3.5 when sending to a local mail server

In our network, we have na IBM Lotus Notes server, which handles emails for basedomain.com. Recently we introduced a new IIS Smtp server just for sending automated emails. The Smtp is configured for ...
1
vote
2answers
73 views

Handling Bounced E-mail with Google Apps for Business

We're sending e-mail from our ASP.NET application (we'll call it @example.com). We use Google Apps for Business to send and receive e-mail sent to xxxx@example.com. Problem is, Delivery Status ...
0
votes
0answers
99 views

Postfix Dovecot receive, no send

I've recently set up an email server using postfix and dovecot. On my android phone I can get incoming emails, but I can't use outgoing emails. When I attempt to set up "Can't safely connect to ...
0
votes
0answers
89 views

Exchange 2013 users receiving corrupt attachment from external users

We are using exchange 2013 and some users are complaining that the attachment they receive is corrupt. Actually lots of people are complaining. Our Mail Flow is as follows. External Mail > Google ...
0
votes
1answer
84 views

IIS SMTP Server is taking too much CPU

I am setting up a Windows Server 2012 with IIS for PHP/Mysql-hosting. I soon as I start the SMTP-service (from IIS 6 Manager) the CPU-percentage in Task Manager spikes. First when I got the server, I ...
0
votes
1answer
35 views

Bizzare routing: EITHER accepts emails OR sends depending if NetworkManager is running

Due to an otherwise unrelated hardware failure (long story) I've been forced to return an older Fedora Core system into service as a mail server. It's primary service is as a file server and Samba ...
0
votes
0answers
326 views

lmtp: connect(backend) failed: Connection refused

A long time ago I'm trying to fix this error but I'm still locked, I appreciate any help :). I detail all that I have and what I am trying to do. I am using Cyrus Murder and apparently everything ...
0
votes
1answer
295 views

Exchange 2010 delivery to postmaster 550 5.1.1 User unknown

Exchange 2010 has a distribution group setup called postmaster and the Email addresses associated with it are postmaster@example.com, postmaster@example.net etc Internal emails sent to postmaster ...
0
votes
1answer
61 views

Spamming from Exchange 2003

I am apparently spamming the world (about 1000 a day) but cannot figure out how. Mxtoolbox does not list me as an open relay and I have disabled all relays that I can find. I have run every virus ...
-1
votes
1answer
305 views

Spam Filters - Why does the same message fail via one smtp server but not the other?

I have a PHPMailer script sending email. If sent via postfix localhost it is marked as spam with these headers. Delivered-To: xxxx Received: by 10.58.210.166 with SMTP id mv6csp82473vec; Sun, ...
0
votes
1answer
108 views

Using the same url for incoming (imap), and outgoing (smtp) mail [closed]

I have setup a postfix daemon and I am able to send emails to an account, and I am also able to login via a mail client and get those emails. But what I'm trying to do is use the same url, e.g: ...
1
vote
1answer
26 views

How can I tell my server to allow logins via a mail client?

I am setting up my first sendmail daemon on centos, using virtual domains and emails. So far, I have got it working and emails sent from remote servers will make it to the inbox. The problem I have ...
3
votes
1answer
662 views

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 ...
2
votes
2answers
108 views

MTA handling of too large emails

If an MTA receives an email that exceeds the message size limit, which bevaviour is preferred? What is the default for common mail servers? Reject the email during the SMTP session. The delivering ...