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
24 views

Postfix + php translating email addresses sent to local domains to something@localhost.localdomain

My first question here, if I don't provide sufficient info straight away, please take it easy on me with the downvotes ;-) I'm running a VPS hosted by afterburst.com with OpenVZ I installed and ...
0
votes
2answers
19 views

Mail delivered via server IP not associated with sender

When a sunbirdinc.com account sends an email to an earthlink.net address, the following message bounces back: ToSomeone@earthlink.net host mx1.earthlink.net [209.86.93.226] SMTP error from ...
0
votes
2answers
54 views

Relay access denied (in reply to RCPT TO command) Postfix Issue

I am trying to configure my server for email taking reference form this link: SMTP Relaying Outgoing Mail in Postfix - using Webmin. I used Mandrill smtp server in my case. I have also configured a ...
1
vote
1answer
38 views

Postfix mandatory smtp/smtpd vs “not mandatory” difference and configuration

Three questions: Correct me if I'm wrong: smtpd_tls_mandatory_ciphers => settings for incoming mandatory TLS encryption smtpd_tls_ciphers => settings for incoming opportunistic TLS encryption ...
-2
votes
0answers
13 views

configure sendmail to discard inbound mail sent in error

Management has asked that I set up a sendmail rule to not respond to internet mail sent in error. I think this can be done through ruleset hooks, where an address resolving to $#error can be routed ...
0
votes
2answers
31 views

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: ...
-2
votes
3answers
32 views

How to force Postfix SMTP to use AUTH (SASL?) and reject anonymous connections? [closed]

The following snippet has been added to the main.cf file of postfix: smtpd_sasl_auth_enable = yes smtpd_sasl_security_options = noanonymous smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd ...
-1
votes
0answers
15 views

Need help setting dynamic message-id in headers

I am using software to send newsletters to clients. The software is connected to an SMTP server, which is configured correctly. The issue is the email software I am using does not merge/transfer ...
1
vote
1answer
17 views

Exchange 2003 restrict anonymous smtp access only

On exchange 2003 I want to listen for smtp on port 25 only so that * anonymous login is only allowed from certain internal IPs * authenticated login is allowed from everywhere I can't see how to do ...
1
vote
1answer
28 views

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, ...
0
votes
0answers
11 views

Windows Server 2008 IIS6 SMTP With more than 1 FQDN

I've tried researching this one, but I'm not having much luck on google. What I have is a Windows Server 08 R2 with IIS6 SMTP installed and configured / working 100% perfectly for Domain A. Domain ...
0
votes
0answers
10 views

FreeBSD pf does not allow inbound smtp [duplicate]

I'm trying to figure out why the following simple pf config allows inbound SSH but not smtp (tcp 25). I'm running FreeBSD 10.1-RELEASE-p9, and the SMTP server is postfix 2.11.4. # ...
0
votes
0answers
18 views

Server apparently being exploited to send emails [duplicate]

I have a dedicated server which runs a forum, a couple of wordpress installations and a prestashop ecommerce platform. My datacentre keeps cutting my connection, stating that my server is sending out ...
0
votes
0answers
51 views

php mailer SMTP ERROR: Failed to connect to server: Permission denied (13)

I fixed this error on a dedicated cPanel server by allowing outgoing connections on port 465 on iptables. I'm trying on AWS now, but I can't figure out what's wrong. I stopped SELinux and iptables; ...
0
votes
2answers
57 views

PostFix 550 5.1.1 Recipient not found from external email

This is a new installation. PostFix reports "550 5.1.1" "Recipient not found.", when users exist. User can send email out everywhere. Users can send email to each other through localhost. All ...
3
votes
3answers
70 views

Reject incoming emails that use your own domain as sender

It would be nice to reject incoming emails which use one of my virtual domains as sender address while not being a legitimate user of mine. I know that I can reject incoming emails which use an ...
3
votes
1answer
106 views

postfix: forward all mail except local user ones

I have a website on a server with a postfix mail server to send the site's emails. Let's say the domain is example.com. The site can send mails to mailboxes of his own domain (like ...
1
vote
0answers
50 views

SMTP error : Remote host said: 550 5.7.1 At least one FROM header address not allowed to send mail from IP ADDRESS

We are developing an email sending app, and we allow our users to specify the From: header their emails will be sent from. Let's say our domain is mydomain.com and our client domain is ...
2
votes
1answer
51 views

Postfix : Conditional Header Checks

Here is my SMTP situation. Mail flow is tagged by an online relay provider (!!SPAM!!, !!BULK!!, etc) Mail flow is received by an internal postfix. Transport is configured to relay to our internal ...
0
votes
1answer
70 views

Can't send email on Windows Server 2008 with Mailenable

I've got a VPS running on Windows Server 2008 and I'm using Mailenable as an Email Server for POP3 and SMTP. I've had the VPS since January 2015, its my first time configuring a server by myself, but ...
4
votes
2answers
94 views

Postfix SMTP Relay Configuration Error

For the last day I was searching for solutions for this problem: My postfix(+dovecot) configuration is fully able to receive e-mails and to serve them via IMAP but it fails at accepting them via SMTP ...
3
votes
1answer
40 views

How to reinject scanned mail into the queue using sendmail

I would like to pass incoming mail using virtual_transport to a transport spamassassin (main.cf: virtual_transport=spamassassin) and then reinject the scanned mail into postfix using sendmail. The ...
1
vote
2answers
52 views

How do I setup a server to send emails after starting (i.e. not meaning as an email server)?

Windows Server 2012 R2 w/ GUI, UPS system I am setting up my first server. It is a Hyper-V host that will host multiple VM servers. The system is on a UPS. When the UPS detects an AC power ...
-1
votes
0answers
67 views

Differences between Exchange's “default” SMTP certificate and others enabled for SMTP?

I know that: You can enable the SMTP service for multiple certificates in Exchange The last certificate enabled for SMTP becomes the "default SMTP certificate" My question: What are the ...
3
votes
1answer
23 views

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 ...
1
vote
2answers
43 views

Wildcard MX record support?

Let's say I want to start a service where customers get their own subdomain on my domain for email addresses only. I have an A record for mydomain.com and a CNAME for www.mydomain.com If I add a ...
0
votes
1answer
12 views

Exchange 2013 return message for old addresses

In my company there are two kind of smtp address in exchange 2013 recipients: j.deere@mycompany.com (old) john.deere@mycompany.com (new) Now I would like to remove all old addresses (j.deere) but I ...
-1
votes
1answer
44 views

My server mail going junk in hotmail and yahoo [duplicate]

All my server mails going to spam in hotmail and yahoo. Here is my full mail source. Can any one please help me to sort out this issue ? ...
3
votes
1answer
41 views

How can one configure exim still to reject invalid recipients after an earlier ACL returned “discard”?

For the reasons set out in my earlier question Originating (non-critical) emails from a "less-trusted" host, it unfortunately seems that we must run an SMTP server for the sole purpose of accepting ...
-3
votes
1answer
48 views

How do I set up an MTA to prevent spam relay? [closed]

I'm trying to secure my MTA against relaying spam, and am trying to understand what's involved. For example: Say I send an email using an Yahoo account to a Gmail account. When Yahoo is relaying ...
5
votes
3answers
78 views

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 ...
1
vote
2answers
45 views

Smtp sending via Exchange some mails do not complete but still send - why?

I have an application that sends smtp email via a local Exchange server at a customer. All the email sends ok (it gets to the recipient) but some email gets sent multiple times because my application ...
5
votes
1answer
83 views

postfix dovecot disable lmtp

I have 3 servers. 1 MX server with postfix and 2 dovecot servers. MX server receive emails and then serve them through LMTP to specific dovecot server. All mailboxes from same domain are on same ...
1
vote
0answers
27 views

Postfix relay smtp to 2 relayhosts for same domain [duplicate]

have a setup in which Postfix relays mail for a specific domain to another mail server (Exchange) via the usual transport file: # /etc/postfix/main.cf transport_maps = hash:/etc/postfix/transport # ...
0
votes
1answer
52 views

Configuring Reverse DNS on Windows Server 2008, can't send email

I run a VPS on a Windows Server 2008 machine, and since I got it in January 2015 everything has been running fine, the server has IIS, DNS, and uses Mailenable for email exchange. I've been running ...
0
votes
0answers
22 views

Show blocked SMTP connections in Exchange 2010

Currently, I have an anonymous receive connector set up on my Exchange 2010 system that allows from an entire subnet. I'm looking to change this to only allow from specific IPs, but need to know when ...
1
vote
1answer
50 views

iptables KVM prerouting SMTP

I have a host machine that has to manage traffic on port 25 and route to port 25 on the KVM machine for postfix deamon like this scheme: WAN --> (25) HOST_MACHINE --> (25) ...
0
votes
0answers
70 views

ubuntu firewall blocking smtp tasks, port 465 is open

I have been trying to get my Wordpress site able to send emails, and it DOES WORK but only work if I turn off the firewall. I am using UFW. However, I do have port 465 (connecting to gmail) open while ...
1
vote
1answer
53 views

OpenVZ - SMTP - telnet - Connection timed out

I have problem with SMTP in my OpenVZ container. I've created OpenVZ container by Proxmox on dedicated server in OVH. This container will be as mail server. So I create on "mother-server" rules to ...
1
vote
2answers
160 views

Can't communicate with SMTP server from particular machine

Here is the situation: When I run the following on my local machine, the mail server responds: $ telnet mail.server.com 2525 Trying <mail.server.com IP>... Connected to mail.server.com. ...
0
votes
1answer
48 views

How would get an email server reputation via cli or script?

I am trying to monitor email server reputation via cli or script i.e. https://www.senderbase.org/ I found a way supposedly to do it via dig, but the output appears to be very incorrect. It indicates ...
0
votes
0answers
55 views

Major Mail Issue - SMTP Local Server Not Working

My database (MySQL), web server (IIS 8 ) AND SMTP server (IIS 6) are all on the same dedicated server (Windows Server 2012) that I'm honestly renting for a bit of system admin practice. I followed a ...
2
votes
1answer
42 views

Authentication error connecting to a mail server via openssl in the terminal

I've set up an email server using Postfix and Dovecot and I'm able to send and receive mail using various mail clients but for some reason I get an authentication error when I try to connect via ...
1
vote
1answer
32 views

How to set the username and password for smtpd in Postfix?

I've set up Postfix as SMTP server by adding this configuration to main.cf: myhostname = foo.com mydomain = foo.com myorigin = $mydomain smtpd_sasl_path = private/auth smtpd_sasl_auth_enable = yes ...
2
votes
2answers
158 views

How to set up TLS on hMailServer?

Complete noob here. Please be gentle :) I have a Windows 2008 server, running hMailServer. Right now all my communication is unencrypted. I want to start using TLS. So now I've got myself a SSL ...
0
votes
2answers
53 views

sendmail: why the error codes from error:nouser and no user differ?

With sendmail 8.14, when there is no user at a given domain, the error that sendmail seems to produce is as follow: 550 5.1.1 <info@example.su>... User unknown However, if you use the ...
0
votes
2answers
109 views

How to enable CentOS 7 to connect to an external SMTP? [closed]

I have a web application deployed in a webserver, running on a CentOS 7. This web application sends e-mails through an external SMTP (in-v3.mailjet.com, port 587). How can I enable CentOS to connect ...
-2
votes
1answer
67 views

Will exchange server receive emails with wrong address [closed]

Say if I sent an email to user@theirdomain.com, the exchange server and the user will receive it, but if I sent an email to fakeuser@theirdomain.com using SMTP client, there will be no fakeuser ...
2
votes
0answers
55 views

nullmailer swaps sender and recipient

I want to send emails from my server through external mail server. So I installed nullmailer as one of simpliest MTA in Debian 7 x32. My /etc/nullmailer/remotes: smtp.example.com smtp ...
0
votes
1answer
167 views

Postfix STARTTLS only on port 25

I want to enable STARTTLS on port 25, but for unknown reasons it only works on port 465. master.cf: smtp inet n - - - - smtpd -o syslog_name=postfix/smtp -o ...