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    GuideDomain VerificationCustom Return Path

    Configure Custom Return Path (MX & CNAME)

    Configure custom MX and CNAME records to handle bounce processing and delivery feedback loops securely on behalf of yourdomain.com.

    Overview

    A custom return path (also known as MAIL FROM domain alignment) routes bounce and complaint feedback signals from sent emails back to Simply Send's logging infrastructure. Since Simply Send delivers emails over a hybrid multi-cloud infrastructure, you must configure alignment records for both providers:

    • AWS SES delivery routes utilize a dedicated **MX record** on the return-a subdomain to map bounce notifications back to AWS servers.
    • Oracle Cloud (OCI) delivery routes utilize a dedicated **CNAME record** on the return-o subdomain to route telemetry feedback through Oracle servers.

    Aligning these return path domains to subdomains of your primary verified sending domain satisfies strict DMARC alignment criteria, significantly boosting deliverability and preventing messages from landing in spam folders.

    Step 1: Retrieve Your Return Path Records

    Log in to Simply Send, go to the Domains page, select your domain, and navigate to the DNS Records page. Under the Email Authentication section, you will find both Custom Return Path record specifications.

    Step 2: DNS Record Specifications

    Add the following three records to your registrar's DNS configuration panel:

    Record TypeHost / NameValue / Points toPriorityVerification Status
    MX (AWS SES)return-a.yourdomain.comfeedback-smtp.us-east-1.amazonses.com10Mandatory
    TXT (AWS SES)return-a.yourdomain.comv=spf1 include:amazonses.com ~all-Mandatory
    CNAME (OCI)return-o.yourdomain.comregionCode1.rp.oracleemaildelivery.com-Mandatory

    Step 3: Configuration Guide & Critical Considerations

    CRITICAL WARNING: Do not overwrite your root MX records

    You must add the AWS MX and TXT records strictly to the **subdomain** (e.g. return-a or return-a.yourdomain.com), and NOT on the root domain apex (@ or left blank).

    Adding the MX record to your root domain will override your primary incoming mail servers (e.g. Google Workspace or Microsoft 365), which will break your business's regular incoming email delivery.

    OCI Return Path CNAME Details

    The OCI CNAME record value utilizes a region-dependent routing prefix (e.g. iad1 for Ashburn, phx1 for Phoenix). Ensure you copy the exact value displayed in your dashboard to match your account's deployment datacenter.

    Example AWS DNS Settings:

    Host: return-a.yourdomain.com
Type: MX
Value: feedback-smtp.us-east-1.amazonses.com
Priority: 10
    Host: return-a.yourdomain.com
Type: TXT
Value: v=spf1 include:amazonses.com ~all

    Example OCI DNS Settings:

    Host: return-o.yourdomain.com
Type: CNAME
Value: iad1.rp.oracleemaildelivery.com

    Step 4: Verify and Activate

    Wait for Propagation

    DNS record changes propagate across global caching servers in a few minutes, but can take up to 24 hours.

    Enable in Console

    Once propagation finishes, select "Verify Domain" in your Simply Send console to enable return-path alignment.

    Next Step: Link Tracking Setup

    Now that your delivery routes are configured, set up optional custom link redirection CNAME records to track recipient click behavior.

    Configure Link Tracking

    Domain Setup Complete!

    With SPF, DKIM, DMARC, custom MAIL FROM MX, and Click Tracking configured, your domain is fully authenticated and brand-aligned.

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