Hey, @Cox technical people, something in your filters have changed!
I am beyond frustrated with spending hours on the phone over the past week with Cox reps who cannot solve this, and are unwilling to escalate to real technical IT people who can. It's not an Outlook problem! If I had a choice, I'd have already dumps Cox. Eventually, the Cox monopoly will evaporate and people will remember their lack of customer support.
I have used the same email address and Outlook setup for years. It has worked (until last week). Now, I cannot send an outbound email via outlook, When I do, here is the bounce back email response I get:
From: System Administrator
Subject: Deliverable: Test
Your message did not reach some or all of the intended recipients.
Sent: 5/23/2020 9:00 AM
The following recipient(s) cannot be reached:
'firstname.lastname@example.org' on 5/23/2020 9:00 AM
550 <email@example.com> sender rejected. Refer to Error Codes section at https://www.cox.com/residential/support/email-error-codes.html for more information. AUP#CXSNDR
And, the 550 error code on the COx website says:
"550 - [<mailfrom address> sender rejected] - Cox requires that all sender domains resolve to a valid MX or A-record within DNS. - Ensure that your domain has a valid MX or A-record within DNS.
Anyone have any ideas?