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Cox is now blocking/dumping forwarded emails

Dear Cox. I have my personal email address that I've used for decades. It is simply forwarded to my address by dns provider ( I then retrieve my emails from cox servers. Worked till yesterday. (In the past, however, I've had enormous trouble with cox spam filters tagging my outgoing emails sent from a non-cox return address as spam. I still do after 7 pages of discussion on this very forum listening to cox techies pointing fingers on others.)

But as of yesterday even simple forwarded emails all started disappearing.

According to since today ALL of their clients with COX addresses started seeing their forwarders go dead. No bounce message, nothing, but all forwarded emails to cox addresses just go into oblivion. For ALL directnic clients email forwarding with cox addresses, not just me. For other providers directnic forwarding still works just fine. They don't know what the problem with cox is now.

Called cox and of course finger pointing is the name of the game. So please cox, what did you do this time? What did you do this time? Please what did you do this time?

  • Can provide any headers from the forwarded email?

    Also, can you send a email from your domain to your address? If not, do you get any bounce backs? If not, can you include the headers from that test email? 

    Last, what is the domain. Their SMTP servers might be blacklisted somewhere, causing Cox to firewall the domain.

  • To add. Just set up a new ms outlook email account. Also set up an additional forwarding rule for my primary email address (at directnic) to go to this new outlook email. Tested - my email was forwarded by directnic to outlook and was received there no problem - but the forwarding to COX's again vanished into nothingness. So it means directnic's forwarding works fine. It also means that Cox is now doing something to block/dump forwarding from other addresses.

    Why would you do that, Cox???

    Just found a thread on this forum from Dec. 9 claiming that his forwarding from Gmail also started getting dumped by Cox. Anyone else can come forward with similar problem?

  • Yes, email sent to address goes through. It's forwarding that is being dumped. Domain is, not blacklisted anywhere as far as I can tell. Directnic ips are unlikely blacklisted either (just forwarded to outlook, see my other post)

  • This is a gmail support article, but I assume it applies to anyone forwarding from one domain to another. Could it be relevant? We can tell more about what is going on, but need to see the email headers.

    "We recommend that you do not change the envelope sender when forwarding email to Gmail. Sometimes, when forwarding email, the envelope sender gets changed to your domain. When this happens, Gmail may learn that your domain is sending spam, and will treat other emails from this domain as spam as well.

    Alternatively, changing the envelope sender is ok if you do one of the following:

    • Put "SPAM" in the subject
    • OR discard any spam emails and not forward them to Gmail at all.

    SpamAssassin is a free spam filter that can be used for identifying spam outside of Gmail, and putting "SPAM" in the subject.


    • Do not modify, remove or shuffle message headers or modify the body of the message. DKIM or DomainKeys signatures will break if the body is altered, and all authentication information will be lost.
    • Common DKIM breakages include modifying the mime boundaries, anti-virus or anti-spam programs modifying the body of the message, expanding the message recipient using LDAP, and re-encoding the message.
    • Several highly-phished domains have asked Gmail to enforce strict authentication checks on their mail. These domains include eBay, Paypal, and Google. If your mail server modifies the forwarded messages from these domains, these messages will be marked as phishing.
    • One symptom of this problem is that a messages from these domains forwarded through your mail server to Gmail will have an Authentication-Results header that show that DKIM did not pass, while messages sent directly to Gmail will have a passing signature.


  • Sorry, I fail to see relevance of this gmail article to the case at hand. I have no mail service from directnic, only email forwarding to my cox address. No headers to show you. And Directnic forwards fine, as I tested with new outlook account, but just not to Cox address anymore. Directnic likely forwards to Cox, but then the email goes into oblivion before or when or after it reaches Cox service. Just started happening.

    1. Directnic claims ALL their clients with COX addresses just started seeing their forwarding fail, whereas their forwarding to all other email addresses works fine.

    2. I confirmed #1 point myself with test forwarding thru Directnic to outlook email address.

    3. Dec. 9 post on this very forum reports that his forwarding from Gmail to Cox address no longer worked all of sudden.

    How many more clues does one need to begin suspecting Cox's recent "foul play" in the causation of this issue? Pointing fingers on others is pointless. But if this problem is not fixed, Cox is de facto denying me mail service. Am I not paying enough?