Knowledgebase of all things email


How to add a DKIM record to your domain

To reduce the risk of your emails ending up in a spam folder, it is important that you authenticate the service you send via to use your domain name.

How to add a SPF record to your domain

To reduce the risk of ending up in a spam folder when you send emails, you should allow the service you send via to use your domain name.

How to add a Sender Domain to Userlist

In order to use your own domain name to send emails from Userlist you need to add a Sender Domain to the application.

How to set up DMARC on Mailerlite

Adding a sending domain to your Mailerlite account is an important step to take in order to ensure DMARC compliance, and here's how to do it.

How to set up Google Postmaster Tools for your domain

Adding your domain to Google Postmaster Tools is fairly easy. Just follow this guide to access spam rate reports for your domain.

How to set up a custom Return-Path

Setting up a custom return path is an important step to take in order to ensure DMARC compliance, and here's how to do it if you use Postmark.

How to verify your domain

Imagine if your competitor could set up a newsletter in your name and send emails from your domain? To prevent that you must verify your domain.


Bulk Email

When the same email message is sent to multiple recipients it's considered Bulk Email. This isn't necessarily spam, however.


DKIM lets email servers to verify the authenticity of an email. It uses DNS record lookups to verify the sender of a given email.

DMARC: Domain-based Message Authentication, Reporting & Conformance

DMARC is a way to let recipient servers know what email servers you send emails from, and what they should do if they receive an email not sent from one of your servers.

DNS: Domain Name System

DNS is the phone book of the internet. Whenever you type a domain name into your browsers address field, the browser asks DNS what computer it should contact in order to get the website, you've requested.

Email Service Provider

The service provider you hire to send and/or deliver your emails. They'll run email servers and spam filters for you, and many provide a web interface.

Email client

Your email client is the program you use to read and send emails with. For most people this means something like Outlook, Gmail, or Apple Mail.

Email server

An email server is a computer capable of both sending and receiving emails. It connects to other email servers on your behalf to deliver your emails.

Google Postmaster Tools

Postmaster Tools gives you detailed reports about emails received by Gmail and Googles other email services.


Pyzor is a collaborative system used to detect bulk and spam emails. It is run by your email service provider, often as part of SpamAssassin.

SNDS: Smart Network Data Services

SNDS is Microsofts online portal that gives email senders access to data about emails received by


SPF is a DNS record that contains information about what servers are allowed to send email for a domain.


Spam is defined as unsolicited marketing emails, although a more common definition is "all those damn emails I don't want to receive".


A popular spam filter used on many email servers. It works by running a bunch of tests and uses a summary score to evaluate the spamminess of an email.


When someone sends an email pretending to be sent from someone else, it's called spoofing. This is commonly used in phishing attacks.

Frequently asked questions

What is

When setting up your domain on Mailchimp, you might be asked to configure a CNAME record for

What is

If you see an email with it's being sent using Postmark as ESP. They use the domain for tracking bounced emails.