Multiple SPF records on a domain — how to fix

What's wrong

A name may have exactly one TXT record starting with v=spf1. With two (often an old one plus one added per a new service's guide) receivers return permerror and SPF stops working entirely.

How to fix

Merge the mechanisms into one record and delete the other:

; before
example.com. TXT "v=spf1 include:_spf.google.com ~all"
example.com. TXT "v=spf1 include:sendgrid.net ~all"
; after
example.com. TXT "v=spf1 include:_spf.google.com include:sendgrid.net ~all"

• all appears once, at the end.
• Mind the 10-lookup limit — see SPF: more than 10 lookups.
• The legacy SPF record type (99) is not needed — TXT only.

Verify with Email DNS Checker.