How do I setup domain authentication with different email and website domains?

Key findings

• From address alignment: The domain you use in the "From" address of your marketing emails is the one that needs to be fully authenticated. This includes setting up DKIM (DomainKeys Identified Mail) records correctly.
• DNS record placement: All necessary DNS records (like CNAMEs for DKIM) must be published in the DNS zone of the domain that matches your "From" address, not your website domain, if they are different.
• Inbound mail capability: For successful domain verification and to handle replies or bounces, the domain used in your "From" address must be capable of receiving email (i.e., have an active mailbox or mail forwarding set up).
• Provider-specific requirements: Email service providers (ESPs) like Mailchimp have specific processes for domain verification and authentication, often involving sending a verification email to an address at the sending domain.

Key considerations

• Brand consistency: While technical setup dictates using the email sending domain, consider using a domain for marketing that your customers recognize, even if it differs from your internal email domain. This often means using your website domain as the sending domain for marketing communications.
• Future sender requirements: Major mailbox providers like Google and Yahoo are increasingly stringent, requiring CNAME records to be in the same domain space as the "From" address for proper DKIM alignment and improved deliverability.
• Technical vs. marketing domains: Distinguish between the domain used for internal company email addresses and the domain intended for marketing communications. The latter is what needs comprehensive authentication setup (SPF, DKIM, DMARC).
• Domain verification: Ensure you can receive verification emails at the domain you intend to send from. Mailchimp (and most ESPs) will send an email to an address at that domain, which you need to access to complete the setup. See their guide on how to verify a domain.
• Subdomain strategy: Consider using a subdomain (e.g., email.yourdomain.com) for marketing emails to isolate its reputation from your main website or corporate email domain. Learn how to set up email subdomains.

Key opinions

• Domain for marketing: Marketers prefer to use the domain customers are familiar with (typically the website domain) for marketing emails, even if internal emails use a different domain.
• Verification process: The primary hurdle for authentication is often the domain verification step, which requires receiving an email at the domain intended for sending.
• CNAME records location: CNAME records for DKIM authentication must be added to the DNS settings of the domain that will be used for sending marketing mail.
• Email receiving capability: It is essential to have an email account or forwarding set up for the sending domain to handle verification emails, replies, and potential bounces, which impacts overall deliverability.

Key considerations

• Aligning authentication: The domain in your DKIM (d=) signature and your SPF alignment should match the domain in your "From" header (RFC 5322.From) to avoid deliverability issues. This is especially true when setting up authentication for multiple ESPs.
• Setting up inbound mail: If the website domain is chosen for marketing, ensure it can receive mail to complete verification and manage customer interactions. This might involve adding a user to an existing mail service like Google Workspace, or setting up new MX records.
• Understanding ESP terminology: Be aware of how your ESP differentiates between "domain verification" (proving ownership) and "custom authentication" (DKIM/SPF setup). Mailchimp provides guidance on setting up email domain authentication.
• Avoid typos: Careful attention to detail is critical when configuring DNS records and email addresses to prevent errors that could hinder authentication and deliverability.

Key opinions

• DKIM alignment: The "d=" tag in the DKIM signature must match the domain in the RFC 5322.From header of the email for proper authentication.
• Future requirements: Upcoming changes (e.g., February 2024 for Google and Yahoo) mandate that CNAME records must be in the same domain space as the "From" address to avoid email blocks.
• Impact of missing mailbox: If no mail service is set up for the "From" domain, email delivery will be significantly negatively affected, as recipients cannot reply and bounces may not be handled properly.
• Inbound mail necessity: Handling inbound mail for the sending domain is crucial for replies and general email management, making it an essential first step in setting up authentication.

Key considerations

• Technical setup for mail receiving: Ensure that the domain used for sending email (your "From" domain) has proper MX records and an active mailbox or forwarding system configured to receive mail. This is vital for effective DMARC, SPF, and DKIM setup.
• DNS record placement: DNS records, particularly DKIM CNAMEs, must be published in the domain that corresponds to the email's "From" address. This ensures that the sending domain is correctly authenticated.
• Proactive compliance: Stay informed about upcoming changes in email authentication requirements from major mailbox providers to maintain optimal deliverability and avoid being blocklisted (or blacklisted). Understanding what happens when your domain is blocklisted is critical.
• Seek specific advice: If encountering complex issues, consult with your ESP's support or a deliverability expert for precise guidance tailored to your setup.

Key findings

• Dedicated sending domains: Many ESPs recommend or require setting up a dedicated sending domain for marketing and transactional emails to ensure optimal deliverability and reputation.
• DNS record types: Authentication primarily involves adding CNAME or TXT records to your DNS provider, linking your sending domain to the ESP's authentication infrastructure.
• Verification methods: Domain verification typically involves receiving a confirmation email at an address on the domain or adding a specific TXT record to your DNS.
• Importance of authentication: Domain authentication (SPF, DKIM, DMARC) is strongly recommended by documentation to prevent emails from being marked as spam or blocked entirely by recipient mail servers.

Key considerations

• Account login: You will need access to your domain's DNS settings (through your domain registrar or hosting provider) to add the required authentication records. This is where you would set up SPF and DKIM records for new subdomains.
• Propagation time: After adding DNS records, it may take some time (up to 48 hours) for changes to propagate across the internet before authentication can be fully verified.
• Multiple authentication types: Some ESPs offer different authentication options, such as CNAME (preferred for easier management) or TXT records. Understanding these options is key.
• Troubleshooting: Documentation often provides troubleshooting steps for common authentication issues, such as incorrect DNS entries or delays in propagation. This knowledge is important for troubleshooting SPF authentication issues.