
The ARC Header: How Forwarding Breaks DMARC and What You Can Do
Forwarders break DMARC by modifying messages in transit. ARC (RFC 8617) preserves authentication results across hops. How it works, who supports it, and the limits.

The complete compliance checklist for Yahoo and Gmail's February 2024 bulk sender requirements. Authentication, unsubscribe, complaint rates—what you actually need.

Forwarders break DMARC by modifying messages in transit. ARC (RFC 8617) preserves authentication results across hops. How it works, who supports it, and the limits.