Tag Archives for " SMTP "

Release hold queue email in Postfix – postsuper

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How to flush Postfix’ mail queue from the command line and delete all mail from the queue? Easy, use the Postfix postsuper command as explained in this post. The postsuper command controls different types of queues in the Postfix mail system, like the deferred or hold queue. This post shows you some Postfix queue operations to maintain your mail servers.

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Send authenticated email over TLS from Zen Cart

Zen Cart is an open source shopping cart software. Unfortunately, Zen Cart has had some difficulties in the past sending authenticated SMTP email from a website. Here is how to let Zen Cart send email over an encrypted TLS connection, when the following condition is met: StartTLS is required. Since Zen Cart v1.5.2 StartTLS support is available.

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Monit monitoring on Ubuntu 14.04 VM on Hyper-V

Monit monitoring for websites and services, on an Ubuntu 14.04 LTS VM, hosted on a Windows Server 2012 R2 or Windows 8.1 Hyper-V. This post is about setting up a Monit monitoring service. Monit is a free and open source service monitoring application which can perform various event-based actions. Monit can send email notifications, restart a service or application, or take other responsive actions. We […]

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Send authenticated SMTP email over TLS from WordPress

How to configure TLS for SMTP email in WordPress. I was suprised WordPress is not able to send email using an SMTP server out-of-the-box. Not to mention using authenticated SMTP or TLS transport for security. A quick Google search showed me multiple plugins to handle this, but I wanted to create something myself. Here is how to override the wp-mail() function and send email using […]

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Send email with Ghost using SMTP authentication and TLS encryption

How to send email with Ghost publishing platform, with SMTP authentication over a TLS encrypted connection. Nodemailer is module for Node.js, for sending out emails, with support included for Unicode, HTML, SMTP, XOAUTH, SSL and TLS

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SMTP over Hidden Services with postfix

This post is about sending SMTP traffic between two servers on the Internet over Tor, that is without someone being able to easily see who is sending what to whom.

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How to delete all MAILER-DAEMON emails in Postfix queue

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How to delete all MAILER-DAEMON emails from your Postfix queue, when it matches a sender or recipient email address condition. When a large scale spam run was sent through your mail servers, you need to clean up and remove those spam messages. Doing so guarantees normal, valid email messages being sent quickly, and the spam messages never leave your queue. In Postfix, there are various […]

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How to test SMTP Authentication and StartTLS

How to investigate and resolve StartTLS/TLS authentication issues on SMTP, IMAP, POP3 servers with the openssl client library, using the command line

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Add (custom) headers to MailMessage class

How to add custom headers to System.Net.Mail? When sending an email using the MailMessage class (System.Net.Mail namespace) in an ASP.NET website, certain email headers like Message-ID are not always set. When a Message-ID header is missing, email might be blocked by the recipients SMTP server. Therefore it is necessary to set such headers…

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How to send authenticated SMTP + TLS in PHP, ASP and ASP.NET

Authenticated SMTP and TLS script examples for ASP, PHP, ASP.NET (C#/VB.Net): if you want to send secure email from your website, over an TLS-encrypted connection, this post is for you! In this post I’ll provide some code examples that you can use to send secure, and authenticated, SMTP email from your website.

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DMARC: “Domain-based Message Authentication, Reporting & Conformance”

Just came across DMARC.org, which looks like a promising specification to fight email-based abuse. From its website:

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