digitalFAQ.com Forum - Optonline.net email bouncing (550 5.7.1 Unacceptable greeting)

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Optonline.net email bouncing (550 5.7.1 Unacceptable greeting)

If you use Optonline.net (OOL), you may not be getting emails from digitalFAQ.com right now.

For reasons unknown to us, as well as OOL's own techs (!), we're getting this odd error:

Code:

This message was created automatically by mail delivery software.



A message that you sent could not be delivered to one or more of its

recipients. This is a permanent error. The following address(es) failed:



  x@optonline.net

    host mx.optimum.net [167.206.4.77]

    SMTP error from remote mail server after MAIL FROM:< @digitalfaq.com> SIZE=4591:

    550 5.7.1 Unacceptable greeting x.in-addr.arpa from host x :

    rejected - 01

^ Note that this has been partially scrubbed.

I just got off the phone with them, and it's being escalated to network engineers. Supposedly we'll hear back from OOL in 24-48 hours.

FYI, this is one reason that ISP emails are terrible. The main two are:

1. They over-block. Lots and lots of false spam bounces. You're not getting valid emails!!!
2. When you move, you lose your address.

Your own custom email is best, either with a hosted account or even your own server. Then you control everything that goes on, and get to have your own vanity address (me@myname)

And next best is the freemail: Gmail, Outlook/Hotmail, Yahoo, etc.

Still bouncing.
Still not contacted us with an update.

It was more than 48 hours, but they did get back to me.

I'm not able to talk directly to the engineer, and have to proxy communication through a basic support tech. The message was that the greeting is wrong, and breaks RFC 5321, and left it at that. "Do that" to fix it, and get an HELO. But the error still is not making sense, as other services that check for greeting compliance (SpamExperts, for example) are not giving rejections.

In fact, looking at the error again, it was first rejected due to RFC 822 (in-addr.arpa), which then triggered RFC 5321 (though I'm not sure why). Many PTR (reverse DNS) use a simple 4.3.2.1.in-addr.arpa as the reverse of 1.2.3.4 serve IP. However, this is not required. Refer to RFC 2317, which explains classles in-addr.arpa. That's what Namecheap is using for server default PTR. For example, 4.0-9.3.2.1.in-addr.arpa. Note the 0-9.

I don't think Optonline/Cablevision's services are configured properly, and thus are giving us false rejections.

I've reported this, and await their findings.

When you look up the PTR with online tools, as well as the greeting (HELO/EHLO), everything passes. And there are no other problems with any other service.

Decyphering RFC isn't easy when you've not really done it for several years. (ie, The server just works, easy to forget how to solve problems when you have none! Thanks Namecheap!)

This started to happen again about a week ago. :rant:

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