Email Forwarding and DMARC: Why Forwarded Emails Sometimes Fail, and How to Fix It

Estimated reading time: 5 minutes

Email forwarding is a common practice in both personal and professional settings. Whether you’re consolidating inboxes or routing customer messages to the right team, it’s a simple and useful tool. However, behind the scenes, forwarding can cause unexpected issues, especially when combined with modern email authentication systems like DMARC.

If legitimate emails from your domain are getting lost, rejected, or marked as suspicious after being forwarded, DMARC might be the reason why. Let’s take a closer look at how forwarding interacts with DMARC, why problems happen, and how you can fix them.

What Is Email Forwarding?

At its core, email forwarding just means automatically redirecting a message from one address to another. For example, you might forward emails sent to hello@yourdomain.com to your main inbox at you@example.com. It helps keep communication centralized and makes inbox management easier.

However, forwarding changes the way an email is delivered. While it seems straightforward to the sender and the final recipient, there are important technical changes in the background that can affect how email servers interpret the message.

What Is DMARC and Why Does It Matter?

DMARC (Domain-based Message Authentication, Reporting and Conformance) is an email security protocol designed to protect your domain from being misused or impersonated. It builds on two other protocols:

• SPF (Sender Policy Framework): Verifies that the email is sent from a server allowed by your domain.
  
• DKIM (DomainKeys Identified Mail): Uses cryptographic signatures to ensure the message hasn’t been tampered with in transit.

DMARC uses the results of SPF and DKIM checks to decide how to handle a message. If a message fails those checks, DMARC tells the receiving server to either let it through, mark it as suspicious, or reject it entirely, depending on your domain’s DMARC policy.

The Problem with Forwarding and DMARC

When an email is forwarded, it often fails SPF checks because the forwarding server (the one doing the redirection) isn’t listed in the original domain’s SPF record. And unless that server re-signs the message with DKIM, which most don’t, DMARC has no solid proof that the message is legitimate.

To put it simply, forwarded emails can look suspicious to receiving servers, even if they’re completely legitimate. If your DMARC policy is set to something strict like p=reject, those emails might never reach the final inbox.

Why This Can Affect Your Email Deliverability

These forwarding issues can have real-world consequences:

• Important customer emails might go missing.
• Team members may not receive internal updates.
• Your domain’s reputation could suffer over time.

In some cases, this can even lead to reduced trust in your communications, especially if clients or partners start missing key messages. Test your email deliverability on a regular basis with GlockApps.

How to Fix (or Avoid) Forwarding-Related DMARC Issues

Thankfully, there are practical ways to deal with this. Here’s what you can do:

1. Start with an Easier DMARC Policy.

If you’re just starting to use DMARC, it’s a good idea to begin with a policy like p=none. This allows you to monitor how your emails are performing without affecting deliverability. Over time, you can move to stricter policies like quarantine or reject once you have more visibility.

2. Make Sure SPF and DKIM Are Set Up Properly.

A well-configured SPF record that includes all your legitimate sending services is essential. In parallel, ensure DKIM is signing all outbound messages. Even if forwarding breaks SPF, DKIM can sometimes carry enough weight to keep DMARC from failing, provided it’s intact.

3. Educate Your Teams or Clients About Forwarding.

If people are forwarding emails manually or through personal inbox rules, it’s worth letting them know about potential issues. If possible, encourage direct delivery or use tools that are compatible with ARC.

4. Regularly Review DMARC Reports.

DMARC provides feedback reports that show which messages passed or failed, and why. Reviewing these reports helps identify where forwarding problems are happening, so you can take action. Use a reliable tool like GlockApps’ DMARC Analyzer and get 10,000 free DMARC reports now.

Final Thoughts

DMARC is an essential tool for protecting your domain and email reputation. But like many good security systems, it can sometimes be too strict, especially when email forwarding gets involved.

By understanding how forwarding interacts with DMARC and by making a few strategic adjustments, you can ensure your emails stay secure and get delivered, even if they take a slightly unconventional path to their final destination.

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