Summary
Understanding email headers is crucial for troubleshooting deliverability, authenticating senders, and ensuring proper email rendering. Resources range from guides and webinars explaining header components and authentication to online analyzer tools and technical documentation. Key headers include 'From,' 'To,' 'Subject,' 'Authentication-Results,' and 'Received.' Analyzing these, along with SPF, DKIM, and DMARC records, and understanding 'X-' headers helps diagnose issues. Vendor-specific documentation aids implementation, while RFC standards provide technical details.
Key findings
- Header Components: Key headers include 'From,' 'To,' 'Subject,' 'Date,' 'Message-ID,' 'MIME-Version,' 'Content-Type,' 'Authentication-Results,' 'Received' and 'Return-Path'.
- Authentication Importance: SPF, DKIM, and DMARC results in headers are vital for authenticating senders and avoiding spam filters.
- Troubleshooting Deliverability: Analyzing 'Received' headers traces the email path and helps identify potential spam filter flags affecting deliverability.
- Analyzer Tools: Online header analyzer tools automatically parse headers and highlight deliverability metrics.
- RFC Standards: RFC Editor provides technical standards for the Internet Message Format and header structure.
- Spoofing Prevention: DMARC helps prevent email spoofing and provides mechanisms to monitor and control the use of your domain in email.
- X-Headers: X- headers provide information about the the mail servers configuration.
Key considerations
- Authentication Status: Check 'Authentication-Results' to ensure SPF, DKIM, and DMARC are passing for proper authentication.
- Email Path Analysis: Analyze 'Received' headers to trace the email's path and identify potential bottlenecks or delays.
- X-Headers Context: Consider the specific email systems using 'X-' headers, as they often contain custom information.
- Spoofing Protection: Implement and monitor DMARC records to protect your domain from unauthorized use.
- Documentation Access: Utilize RFC Editor and IETF documentation for detailed technical information.
- Testing Configuration: When testing emails the X- headers provide information about the the mail servers configuration.
What email marketers say
11 marketer opinions
Understanding email headers is crucial for diagnosing deliverability issues, authenticating senders, and ensuring proper email rendering. Email headers act like an envelope, containing essential information about the message's origin, destination, and path. Resources for understanding them range from guides explaining key components such as 'From,' 'To,' 'Subject,' and 'Authentication-Results,' to online analyzer tools that parse headers automatically. A foundational understanding of SPF, DKIM, and DMARC is also critical, as these authentication methods' results are reflected in the headers. Non-standard 'X-' headers can provide custom information, but require knowledge of the specific systems that add them. When testing emails the X- headers provide information about the the mail servers configuration.
Key opinions
- Header Components: Essential headers include 'From,' 'To,' 'Subject,' 'Date,' 'Message-ID,' 'MIME-Version,' 'Content-Type,' and 'Authentication-Results,' each providing specific details about the email.
- Deliverability Diagnosis: Analyzing 'Received' headers helps trace an email's path and identify potential spam filter flags affecting deliverability.
- Authentication Importance: SPF, DKIM, and DMARC records are crucial for email authentication, and their results are reflected in the headers, impacting deliverability.
- Analyzer Tools: Online email header analyzer tools can automatically parse and interpret email headers, simplifying analysis.
- X-Headers: X- headers provide information about the the mail servers configuration.
Key considerations
- Authentication Status: Check the 'Authentication-Results' header to ensure SPF, DKIM, and DMARC are passing, indicating proper sender authentication.
- Email Path: Examine 'Received' headers to understand the email's path and identify potential bottlenecks or delays.
- X-Headers Context: When interpreting 'X-' headers, consider the specific email systems that added them, as they often contain custom or proprietary information.
- Testing Configuration: When testing emails the X- headers provide information about the the mail servers configuration.
- Routing Information: Understand Email headers contain the routing information and metadata for a message and help to authenticate an email’s sender.
Marketer view
Email marketer from Reddit recommends starting with resources explaining SPF, DKIM, and DMARC records to understand email authentication and how it's reflected in headers, as well as using online header analyzers to break down complex information.
27 Sep 2021 - Reddit
Marketer view
Marketer from Email Geeks shares a link to Kickbox's guide to email headers.
27 Dec 2023 - Email Geeks
What the experts say
3 expert opinions
Experts suggest using webinars and dedicated header analysis tools to understand email headers. These resources explain header fields, authentication results (SPF, DKIM, DMARC), and the email's path, which provides insights into potential deliverability issues.
Key opinions
- Webinar Resource: Webinars, like the one by Jennifer Nespola Lantz and Sebastian Kluth, provide detailed explanations of email headers.
- Header Analyzer Tools: Tools specifically designed for email header analysis, such as the one from Spam Resource, dissect and explain the information within headers, focusing on spam detection and authentication.
- Comprehensive Resources: Resources explaining header fields, authentication results (SPF, DKIM, DMARC), and email path analysis can help you understand and resolve deliverability issues.
Key considerations
- Practical Application: Use header analysis tools to identify and address deliverability problems based on header information.
- Authentication Review: Pay close attention to authentication results (SPF, DKIM, DMARC) within the headers to ensure proper sender authentication and avoid spam filters.
- Email Path Analysis: Trace the email's path to identify any potential bottlenecks or delays in delivery.
Expert view
Expert from Word to the Wise shares that tools and resources that explain the meaning of different header fields, authentication results (SPF, DKIM, DMARC), and provide insights into the email's path and potential deliverability issues can be used to understand email headers.
9 Sep 2023 - Word to the Wise
Expert view
Expert from Email Geeks shares a link to a webinar by Jennifer Nespola Lantz and Sebastian Kluth about email headers.
6 Aug 2024 - Email Geeks
What the documentation says
5 technical articles
Technical documentation from Google Workspace, RFC Editor, Microsoft Learn, IETF, and DMARC.org provides resources for understanding email headers. Google Workspace details troubleshooting email delivery with Gmail message headers. The RFC Editor outlines the Internet Message Format. Microsoft Learn explains how to view headers in Outlook. IETF provides specs for the 'Received' trace header. DMARC.org explains how DMARC configuration helps protects from unauthorised email spoofing.
Key findings
- Troubleshooting Guidance: Google Workspace documentation helps analyze Gmail headers to troubleshoot email delivery issues.
- Technical Standards: RFC Editor's documentation specifies the Internet Message Format and header structure.
- Outlook Instructions: Microsoft Learn provides instructions for viewing email headers in Outlook to analyze email flow.
- Email Path: IETF documentation offers technical details for the 'Received' trace header field, crucial for understanding an email's path.
- Email Spoofing: DMARC.org explains how DMARC headers allow you to track the DMARC configuration and protect from unauthorised email spoofing.
Key considerations
- Authentication: Analyze authentication results in email headers to troubleshoot spoofing issues.
- Implementation: Consult vendor specific documentation to help with header implementation and checking.
- Use Appropriate Documentation: Utilize the technical documentation from RFC Editor and IETF for deep understanding.
Technical article
Documentation from RFC Editor describes the Internet Message Format which specifies the syntax for text messages that are sent between computer users, within one computer, or between computers. This includes the message header fields and their structure, providing a technical standard for understanding header components.
18 Sep 2024 - RFC Editor
Technical article
Documentation from Microsoft Learn explains how to view internet message headers in Outlook on the web, detailing the steps to access and analyze the header information for troubleshooting email flow and authentication issues in Exchange Online.
7 Dec 2022 - Microsoft Learn
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