My email to a Cox address blocked as SPAM?
SMTP error from remote mail server after initial connection: 554 cxr-ibgw-6003a.stratus.cloudmark.com cmsmtp XXX.XXX.XXX.XXX blocked. Refer to Error Codes section at https://www.cox.com/residential/support/email-error-codes.html for more information. AUP#CXBL
Unfortunately I don't see "Authentication" in my CPanel so I don't know how to add the suggested DKIM and SPF. I submitted an email to Support about the missing Authentication button, as suggested in the documentation.