Fix "550 SPF check failed": The message failed SPF and was rejected

If your email is bouncing with 550 SPF check failed, it means the message failed SPF and was rejected. Here is exactly what causes it and how to fix it.

What 550 SPF check failed means

This rejection means the receiving server could not verify that your sending IP is authorized in your SPF record. Either your SPF record is missing the sending source, or you have more than 10 DNS lookups.

How to fix 550 SPF check failed

• Add every sending service to your SPF record.
• Keep SPF under the 10-DNS-lookup limit (flatten if needed).
• Pair SPF with DKIM so a single failure does not sink delivery.

How Rainmail helps

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