Forum Discussion

John2222's avatar
Contributor II
3 years ago

Email rejected from me to another customer

 I tried to forward an email today to another Cox user and it was rejected:

            550 <> message rejected. Refer to Error Codes section

at for more information. AUP#CXSNDR

NOTE:  The original email I got was a newsletter which I receive regularly all the time.  This one was marked as --SPAM-- ... in the subject line.

However, just to verify I sent a simple text message to person again, and it went through fine!  What is the explanation for this behavior?

5 Replies

  • John2222's avatar
    Contributor II


    CXSNDR There was a problem with the sender's domain.

    Your email failed authentication checks against your sending domain's SPF, DomainKeys, or DKIM policy.

    • BenS1's avatar
      Former Moderator
      Hi @John2222
      I know how important it is for you to send and receive emails. What you need to do is forward the newsletter that was marked as Spam to this email address: . That will make sure that our system does not flag these messages as spam. The Error Code 550 That you received is saying that our system viewed the message as spam. Let us know if you need any further assistance.
      Ben S.
      Cox Support Forums Moderator
      • John2222's avatar
        Contributor II

        Thank you. Good to know. I forwarded the email as you indicated.  (At least it wasn't rejected this time)