This guide outlines the potential errors you may encounter when sending messages through our service. Each error corresponds to a specific SMTP response with a unique Category, Error Code and Status Code.
Below, you’ll find detailed explanations of these codes, including the causes of the issues and actionable tips to resolve them efficiently. Use this resource to quickly diagnose and address any delivery problems you might be facing.
Blocked
| Category | Code | Enhanced Code | Definition |
|---|---|---|---|
| Blocked | 554 | 5.2.3 | Your email was blocked because there's a policy or rule in place that's preventing the email from being delivered. This could be related to mailbox quotas, email size limits, or specific policies configured by the organization |
DMARC
The message failed DMARC authentication because the "From" header doesn't align with the validated SPF/DKIM domains.
Resolution Tips:
Ensure the "From" address matches the sending domain.
Verify that both SPF and DKIM are correctly configured for your sending domain.
| Category | Code | Enhanced Code | Definition |
|---|---|---|---|
| DMARC | 509 | 5.7.509 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 550 | 5.0.0 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 550 | 5.7.20 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 550 | 5.7.26 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 550 | 5.7.5 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 550 | 5.7.5 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 550 | 5.7.509 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 550 | 5.7.6 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 550 | 5.7.8 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 550 | 5.7.9 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 550 | Missing | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 553 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. | |
| DMARC | 554 | 5.0.0 | The message was rejected by recepients email provider because it did not pass the DMARC. Ensure that the "From" header domain matches or aligns with the SPF/DKIM-validated domains. |
| DMARC | 554 | 5.7.5 | The message was rejected by recepients emai |