Server Fault Stack Exchange
Server Fault Stack Exchange

Questions tagged [smtp]

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.

Some characteristics of SMTP (Simple Mail Transfer Protocol):

  • The default port is TCP port 25 and new submissions (MSA) is port 587.
  • Although depreciated, some services still use port 465 (SMTPS) to support legacy applications.
  • It is used to transmit outbound mail, and mail servers (which listens on port 25) receives mail on port 25.
  • It should not be confused with POP3 / IMAP which is an actual store for the e-mail. SMTP messages are received by the receiving server and then an MTA moves it to the POP3 / IMAP mailbox where it is normally retrieved using a POP3 / IMAP client.

See Also:

RFC5321

3133 questions
1
vote
1 answer

Simple Email Fowarding

Is there a program that handle smtp that has one and only one function: foward email from one email address to another email address? I know that this can be done using virtusertable with sendmail. What I am really looking for is a virtusertable…
kainaw
  • 223
  • 2
  • 11
1
vote
2 answers

Postfix, TLS and StartSSL certificates

I recently changed my postfix installation to use TLS with a certificate issued by StartSSL. I then ran SMTP and TLS checks with no errors or warnings. Everything seemed to work fine. My problem now is, that receiving mails doesn't seem to work in…
Chris
  • 193
  • 1
  • 6
1
vote
1 answer

Postfix SMTP authentication per domain

Is it possible to configure SMTP authentication on Postfix with different user/pass credentials for different domains? So, I have a MTA that relays emails from ~20 different domains. When sending emails to a specific domain, say example.com, my MTA…
kyle
  • 23
  • 1
  • 6
1
vote
1 answer

Exchange 2010 - Unauthenticated users can send/relay local mail via telnet. How to stop this?

I'm completely new to Exchange administration. I have Exchange 2010 installed and working for the most part. The domain in question is mydomain.com. I have checked to make sure the server is not an open relay by testing it through telnet. Mail…
Ivan
  • 198
  • 1
  • 8
1
vote
1 answer

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 Google MX registrys, configure the mail accounts in…
Jovi
  • 33
  • 5
1
vote
1 answer

Exchange 2007 send as different user by default

Allow me to explain in detail. I have a client who runs 3 companies under the same roof. Each user has 3 exchange mailbox accounts (for each company domain) which they load under either Outlook 2007 or 2010. The company has been using…
Mike66350216
  • 277
  • 1
  • 5
  • 12
1
vote
2 answers

Postfix smtp for sending only

The web hosting provider of my company have a mail server with a sending limit of 300 mails a month so the idea is keep using the hosting mail for the mail spool but set up a local Debian server with postfix on it only to send. The idea is configure…
Santi
  • 149
  • 4
  • 13
1
vote
2 answers

TLS connect failed: error:140943FC:SSL routines:SSL3_READ_BYTES:sslv3 alert bad record mac while sending mail via Qmail

I'm trying to send e-mail to one of the biggest polish hosting companies and their servers are refusing to receive it with message: TLS connect failed: error:140943FC:SSL routines:SSL3_READ_BYTES:sslv3 alert bad record mac; connected to…
Spacedust
  • 568
  • 5
  • 13
  • 28
1
vote
1 answer

Postfix "timed out while sending message body" to "Microsoft ESMTP MAIL Service"

For some reason we cannot send larger email to one of our customers. Small emails are fine, but even a message with a 1MB attachment fails to deliver for several hours - Postfix logs keep filling with status=deferred (conversation with…
enkrs
  • 121
  • 1
  • 1
  • 7
1
vote
2 answers

Iptables blocking smtp

Iptables is blocking outgoing and incomming smtp on my server, although I specified it not to. My policies are DROP everything except what's specified. Changing policies to ACCEPT everything "solves" the problem, but I don't want unlimited traffic…
Alex
  • 113
  • 1
  • 5
1
vote
0 answers

Is it possible to prevent emails being sent from an address absent from the AD user's account?

I'm using Exchange Server 2003 on a Windows Server 2003 which is also a domain controller. If a client connects through SMTP using his AD username and password, he can send email from any email address, and not just the email addresses listed in…
Smig
  • 199
  • 1
  • 1
  • 6
1
vote
1 answer

Change email domain OS X Server

I'm having trouble setting up the mail service correctly on my os x leopard server. In server admin, under Mail>General the domain is set to "mydomain.net.nz", and my host name "servername.mydomain.net.nz", yet whenever an account is created, the…
Ryan
  • 268
  • 1
  • 7
1
vote
1 answer

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 emails to be generated, but I've not configured…
Steph Locke
  • 127
  • 1
  • 8
1
vote
1 answer

'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 settings, another function is ok but.. email system is…
Meat Popcicle
  • 11
  • 1
  • 3
1
vote
1 answer

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 mail out. If I send an email from myself to another…
Chase Florell
  • 580
  • 3
  • 14
  • 29
1 2 3
…
99 100