WordPress Email Setup: SMTP, DKIM, SPF, and DMARC Settings

Your key landing pages simply need to work without a hitch if you want to see online success. They collect email addresses, usually in exchange for a whitepaper, a freebie, or access to exclusive content. But here’s the catch — your emails need to be properly authenticated. If they aren’t, they can end up in spam or never reach the recipient at all.

Emails that aren’t received aren’t opened. The result? Lost leads, frustrated users, and wasted effort. So, how do you ensure your emails actually land where they should? Enter SMTP, DKIM, DMARC, and some help from very useful WordPress plugins.

“Do you know what else results in frustrated users, wasted effort, and lost time? Password recovery. It’s another agency pain point we all know and could do without.”
Rocket.net – Password Recovery Tips That Won’t Drive Your Clients Crazy

What is Email Authentication?

Email authentication is a set of protocols and methods that verify the legitimacy of emails sent from your WordPress website. When email authentication isn’t properly configured, your messages might end up in spam folders or fail to deliver entirely.

This typically happens when:

authentication protocols aren’t properly set up

SMTP settings are misconfigured

server restrictions block email delivery

plugin conflicts interfere with sending

Like broken website links, email delivery problems happen. It’s not catastrophic, but as delivery issues accumulate, they can seriously impact your website’s effectiveness – not to mention the potential loss of a customer.

Why Email Authentication Matters

The importance of proper email authentication comes down to three key factors.

First, unauthenticated emails fail to reach your visitors, leading to lost opportunities and frustrated users who never receive the content they requested. And, your marketing team that worked on the whitepaper for the download will be bummed, too.

Second, poor email authentication damages your domain’s reputation with email providers, which can cause even legitimate emails to be flagged as spam. Especially since users train their email clients what they consider spam (by their behavior) you never want to land in the junk folder.

Finally, proper email authentication demonstrates professionalism and reliability. It shows you take communication seriously and respect your users’ inbox space.

When emails fail authentication checks, they typically trigger spam filters or bounce back entirely. These failed deliveries are a wake-up call to review your authentication setup.

Email authentication isn’t optional. With providers like Gmail implementing stricter requirements, proper setup of SPF, DKIM, and DMARC isn’t just best practice. Authentication is essential for reaching your audience.

“Blacklisting can happen for various reasons, such as receiving too many spam reports, sending bulk emails without verifying email lists, or accidental reputation issues.”
WP Mail SMTP

Understanding Email Authentication Protocols

Several key protocols work together to ensure email authenticity:

SMTP (Simple Mail Transfer Protocol)

The fundamental protocol for sending emails — the postal service for your digital messages. It needs proper configuration to function effectively.

SPF (Sender Policy Framework)

A security standard that specifies which mail servers can send emails on behalf of your domain — the approved sender list for your domain. Mailchimp has a great article on SPF.

DKIM (DomainKeys Identified Mail)

Adds a digital signature to your emails, verifying they haven’t been tampered with during transit. It’s the kiss on the back of the envelope.

DMARC (Domain-based Message Authentication)

Sets policies for handling emails that fail authentication checks. This is your domain’s rulebook for email security, connecting your website with your mail provider.

“How do I fix DMARC authentication failure?” support.google.com

Setting Up Email Authentication

The implementation process requires attention to detail but isn’t overly complex.

Setting Up SPF, DKIM & DMARC for Better Deliverability

Access Your Domain’s DNS Settings – Log in to your domain registrar.

Add an SPF Record – Example:

o v=spf1 include:_spf.yourdomain.com ~all

(If you already have an SPF record, merge it with this instead of creating a new one.)

Enable DKIM – Your email provider should provide DKIM keys to add as CNAME records.

Set Up DMARC – Start with a monitoring policy:

o v=DMARC1; p=none; rua=mailto:your-email@example.com;

(Adjust the policy over time based on reports.)

Allow 24-48 Hours for Changes to Take Effect – DNS changes take time to propagate.

Securing SMTP with SSL/TLS Encryption

When setting up email authentication for your WordPress site, it’s crucial to implement SSL/TLS encryption for your SMTP connections. This adds an extra layer of security to your emails.

Using SSL/TLS encryption is increasingly becoming mandatory for email providers to accept incoming mail.

How to Implement

Check if your hosting provider or SMTP service supports SSL/TLS

Update your SMTP settings to use the secure port (usually 465 for SSL or 587 for TLS)

Ensure your WordPress SMTP plugin is configured to use SSL/TLS

Example configuration in wp-config.php:

“`php
define( ‘SMTP_SSL’, ‘tls’ );
define( ‘SMTP_PORT’, ‘587’ );
“`

Online Tools for Email Authentication

Several free tools can help you verify your authentication setup:

MXToolbox: Tests your SPF, DKIM, and DMARC records for proper configuration.

Mail-Tester: Provides comprehensive email deliverability testing and suggestions.

Google Postmaster Tools: Offers insights into how Gmail handles your domain’s emails.

DMARC Analyzer: Helps monitor and analyze your DMARC implementation.

WordPress Plugins for Email Management

Quality plugins can significantly simplify email authentication. Here are two of our favorites:

WP Mail SMTP: The most popular SMTP plugin, offering comprehensive email handling capabilities and OAuth 2.0 support for Gmail.

Post SMTP: A robust alternative with detailed logging and multiple mailer options.

Important Reminder: Check the settings of any plugins running on your website, such as your WooCommerce shop plugin; your plugin’s email settings may also need to be adjusted.

“Review your WooCommerce email settings at WooCommerce > Settings > Email and settings of any plugins that you use to ensure that they send as your branded domain (e.g., me@mybrand.com) and not as your @gmail.com or @yahoo.com address.”
WooCommerce

Best Practice for Email Authentication: Having a Maintenance Schedule

The key to good maintenance is being proactive rather than reactive. Regular monitoring and maintenance prevent small issues from becoming major problems.

Here are the three most important tasks for maintaining sustainable email authentication:

Weekly: Review and respond to authentication failures

Monitor delivery logs and failed authentication reports. You catch problems before they impact your sender reputation or cause delivery issues for multiple users.

Monthly: Authentication tests

Test and review DMARC reports to ensure your configuration remains effective. This check helps identify patterns in delivery problems and keeps your documentation current.

Quarterly: Audits of all authentication records, policies, and protocols

Ensures your entire email authentication system stays up-to-date. Standards and best practices across major email providers aren’t written in stone.

By investing in proper email authentication, you’re ensuring reliable communication with your audience – and protecting your domain’s reputation.

Focus on creating valuable content for your subscribers and let your authentication setup handle delivery.

Wrapping Up

If your WordPress site is sending emails, proper authentication is a must to avoid spam filters and ensure delivery. By configuring SMTP correctly and setting up SPF, DKIM, and DMARC, you improve email deliverability, protect your domain reputation, and keep your communication channels open.

Make these changes today, and never worry about lost emails again!