Mailgun 550 Relay not permitted

The server is not configured to relay messages for the sender's domain.

Understanding Mailgun: A Powerful Email Communication API

Mailgun is a robust email communication API that allows developers to send, receive, and track emails effortlessly. It is widely used in production applications for its reliability and scalability. Mailgun provides a suite of tools to manage email delivery, ensuring that your emails reach the intended recipients without any hitches.

Identifying the Symptom: 550 Relay Not Permitted

One common issue encountered when using Mailgun is the '550 Relay not permitted' error. This error typically manifests when attempting to send an email, and the server responds with a message indicating that relaying is not allowed. This can be frustrating as it prevents emails from being delivered successfully.

Exploring the Issue: What Does 550 Relay Not Permitted Mean?

The '550 Relay not permitted' error occurs when the email server is not configured to relay messages for the sender's domain. This means that the server does not recognize the sender as an authorized user, and therefore, it refuses to forward the email to the recipient. This is a security measure to prevent unauthorized use of the server for sending spam.

Root Cause Analysis

The root cause of this issue is often a misconfiguration in the sender's domain settings. The server needs to be explicitly configured to recognize and authorize the sender's domain to relay emails.

Steps to Fix the Issue: Configuring Your Domain Correctly

To resolve the '550 Relay not permitted' error, follow these steps to ensure your domain is correctly configured:

Step 1: Verify Domain Settings

Ensure that your domain is verified in Mailgun. You can do this by logging into your Mailgun account and navigating to the 'Domains' section. Check that your domain status is 'Verified'. For more details, refer to the Mailgun Domain Verification Guide.

Step 2: Update DNS Records

Ensure that your DNS records are correctly set up. This includes adding the necessary TXT, MX, and CNAME records provided by Mailgun to your domain's DNS settings. These records are crucial for Mailgun to authenticate your domain. For a step-by-step guide, visit the Mailgun DNS Setup Instructions.

Step 3: Check SMTP Authentication

Ensure that SMTP authentication is enabled in your email client or application. This involves configuring your email client to use the correct SMTP server settings provided by Mailgun, including the SMTP username and password.

Step 4: Test Email Sending

After making the necessary changes, test sending an email to ensure that the issue is resolved. If the error persists, double-check your configurations or contact Mailgun support for further assistance.

Conclusion

By following these steps, you can effectively resolve the '550 Relay not permitted' error and ensure that your emails are delivered successfully using Mailgun. Proper domain configuration and authentication are key to preventing this issue. For more information, visit the Mailgun Documentation.

Try DrDroid: AI Agent for Debugging

80+ monitoring tool integrations
Long term memory about your stack
Locally run Mac App available

Thank you for your submission

We have sent the cheatsheet on your email!
Oops! Something went wrong while submitting the form.
Read more
Time to stop copy pasting your errors onto Google!

Try DrDroid: AI for Debugging

80+ monitoring tool integrations
Long term memory about your stack
Locally run Mac App available

Thankyou for your submission

We have sent the cheatsheet on your email!
Oops! Something went wrong while submitting the form.

Thank you for your submission

We have sent the cheatsheet on your email!
Oops! Something went wrong while submitting the form.
Read more
Time to stop copy pasting your errors onto Google!

MORE ISSUES

Deep Sea Tech Inc. — Made with ❤️ in Bangalore & San Francisco 🏢

Doctor Droid