SPF +all — the entire internet can send as you

A record ending in +all authorises every server on the internet to send mail as your domain.

What causes it

• A copy-pasted example record, or a misguided attempt to stop SPF failures by making everything pass.

How to fix it

Change +all to ~all immediately. This is worse than having no SPF record, because it actively vouches for spammers forging your domain.

Check your domain

Also searched for: +all spf, spf pass all danger.