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krash's avatar
krash
New Contributor
6 years ago

Cox email not being delivered to Protonmail

My Cox emails are being bounced back when sent to friends with Protonmail.  All other recipients receive the emails with no issue and my Cox account can receive emails from Protonmail, just outgoing emails are not delivered.  Also, Protonmail support has looked into this and they say they see no issues on why Cox domain is bouncing back emails.

This is the message I get after a few days:

From: Mail Administrator <Postmaster@cox.net>

Date: July 2, 2018 at 7:23:06 PM CDT

To: [my email account] 

Subject: Mail System Error - Returned Mail Reply-To: <Postmaster@cox.net>

Most likely there is a network problem that prevented delivery, but it is also possible that the computer is turned off, or does not have a mail system running right now. Your message was not delivered within 4 days and 0 hours. Host protonmail.com is not responding.

The following recipients did not receive this message:     [recipient's email address]

Please reply to <Postmaster@cox.net> if you feel this message to be in error.

I have forwarded this to postmaster@cox.net, but I feel that's just a generic message.  Any ideas?

3 Replies

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  • ChrisL's avatar
    ChrisL
    Former Moderator
    6 years ago
    @Krash

    The error is indicating that our mail system cannot find theirs. A quick check of their website says they provide secure email hosting out of Switzerland however when I investigate it appears it's actually routed through China. That being the case I suspect something unusual is going on with their hosting records.

    > protonmail.com
    Server: 68.105.28.13
    Address: 68.105.28.13#53

    Non-authoritative answer:
    Name: protonmail.com
    Address: 185.70.40.182
    > set type=mx
    > protonmail.com
    Server: 68.105.28.13
    Address: 68.105.28.13#53

    Non-authoritative answer:
    protonmail.com mail exchanger = 10 mailsec.protonmail.ch.
    protonmail.com mail exchanger = 5 mail.protonmail.ch.

    Authoritative answers can be found from:

    -Chris
    • krash's avatar
      krash
      New Contributor
      6 years ago

      Thanks for the response, Chris.  Would you have any idea why only Cox emails are not being delivered?  I can send emails with no issues from other domains (gmail, yahoo, earthlink, etc.), plus others I know can send emails with no issues.  It seems to be an issue with the Cox domain only.  Thanks.

    • sirhenry's avatar
      sirhenry
      New Contributor
      6 years ago

      im not sure it affects you, but since the end of June, the 26th to be exact. I have been unable to get email from Cox on my iphone. have been calling and chating with tech support and they just keep telling me that they are working one upgrades. so if you like to the outside host using the same settings that I need to use for my Phone, aka POP server and SMTP server then that might be the issue....