SPF lookups

What it checks

How many DNS lookups checking the SPF record takes, its includes followed down, and whether each include has an SPF record.

Why it matters

Receivers stop at ten lookups and treat the record as broken, so every message can fail SPF. Each provider you include costs some.

How to fix it

1. Remove includes for services that no longer send email for you.
2. Replace a and mx with the ip4: and ip6: addresses they stand for.
3. Or send some email from a subdomain, with an SPF record of its own.