If someone with a Gmail address (e.g., [email protected]) sends an email to your domain-based email (e.g., [email protected]), and this address is set up to automatically forward emails to another Gmail address (e.g., [email protected]), the email may fail to deliver.
You may receive a bounce-back error similar to this:
550-5.7.26 This message does not pass authentication checks (SPF and DKIM) and fails DMARC policy
Gmail has strict DMARC, SPF, and DKIM policies. When your server forwards an email originally sent from Gmail (or any strict domain), Gmail sees that:
- Thus, SPF and DKIM checks fail, and Gmail rejects the forwarded email.
- The From address is still the original Gmail sender, but
- The email was forwarded via your server’s IP, which is not authorized to send Gmail messages,
To ensure the most reliable email delivery, avoid auto-forwarding to free email providers like Gmail or Yahoo. These providers often enforce strict authentication policies that can cause forwarded messages to be rejected. Instead, access your domain email directly or use supported mail-fetching methods
