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Q & A Email Authentication · August 21, 2026

My ESP (Mailchimp, SendGrid, etc.) says to add their SPF include. I did, but it still fails.

Check that you have only ONE SPF TXT record at your root domain. If you have two separate TXT records starting with v=spf1, only one is valid and the behavior is unpredictable. Merge all your sending sources into a single SPF record.

Read the full guide
How to Fix SPF Failures (softfail, hardfail, permerror)
SPF softfail, hardfail, permerror, and DNS lookup limit errors each have a different fix. This guide walks through diagnosing each failure type and rewriting your SPF record correctly — without breaking it.
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