Fix "554 5.7.1 (SPF)": SPF returned neutral or fail and the message was rejected

Bouncing with 554 5.7.1 (SPF)? It means SPF returned neutral or fail and the message was rejected.

How to fix it

Fix your SPF record to explicitly authorize the sending source.

Prevent it long-term

• Authenticate with SPF, DKIM and DMARC.
• Send from a dedicated, reputation-clean IP.
• Keep bounce and complaint rates low.

How Rainmail helps

Rainmail sends from your own domain on a dedicated, isolated IP with SPF, DKIM, DMARC, reverse-DNS and managed warm-up handled for you, plus an AI that watches your list health and deliverability — and it welcomes the senders Amazon SES, SendGrid and Mailchimp reject, from $8. Run the free 10-second checker or see plans.