What happens if SPF passes but DKIM fails?
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You're setting up SPF and it's passing, but DKIM keeps failing. Here's what's actually happening to your emails.
The good news: DMARC can still pass if your SPF is aligned with your From domain. That's one of two lanes that work.
The problem: SPF is fragile when emails forward. Some mail systems (Gmail, Yahoo, Microsoft) resend your message through their own servers, and that breaks the SPF check. Once SPF breaks, if DKIM also fails, your DMARC fails too. And that tanks deliverability fast.
The safe move. Get DKIM working. DKIM travels with the email body, so it survives forwarding. Once both are set up, you've got redundancy. If SPF fails in a forward, DKIM still proves it came from you. See also: how SPF, DKIM, and DMARC work together.
Start by understanding why DKIM matters more than SPF for long-term reliability. Then grab a free DKIM checker to see exactly what's wrong with your keys. If you're stuck, the SOS team can diagnose the whole chain in minutes.
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