Server having trouble sending email to hotmail and att addresses - Jan 16, 2018

[mouser]

We have just moved to a new server, and we see that hotmail and att (and maybe some others we haven't found yet), are blocking email from us.
Our new server IP does not appear to be on any blacklists so it may just be they are blocking the server because it's new to them or it is similar to an ip they don't like or they are just being grumpy.
We expect to have it sorted out very soon, but if you try to register an account at the forum or otherwise expect mail from us and don't see, that's why.

I'll post an update here when we see that the emails are going through.

Note that we can still receive mail FROM you, it's just if we send email to your address you won't get it.  So you can still submit comments to us from our Contact page.

[skwire]

Sounds like a reverse PTR record isn't set properly for the mail server hostname that's being used.  Most big-name domains won't even talk to an email server that doesn't have a proper PTR record in place.

[mouser]

Yeah, I've corrected that.  And it seems there was a mis-configuration of the DKIM dns records, which can hurt.  Hopefully all is fixed now.  We shall see.

[mouser]

Att says they have removed the black list, and hotmail says they have as well, so we should be good.

[Shades]

Take a look at website: www.mxtoolbox.com

It shows you on how many different blacklists this domain is registered on. Use the links from their overview to request being removed from each blacklist (separately, I'm afraid). The free version verifies your domain against 30 or so blacklists. If you pay, that list becomes much longer.

Found that website to be very helpful when problems arose with my own mail server.

[mouser]

Yep, that was the first place I went.  Our ip was not on any public blacklists, I think it was just att and hotmail being paranoid by default about an ip they had never seen.

[mouser]

The rewards of getting the SPF, DKIM, DMARC, all configured properly:

[Stoic Joker]

Now that's quite colorful ... Which mail server test gives those results?

[mouser]

Here are the 3 places I used:

• http://dkimvalidator.com
• https://mxtoolbox.com/deliverability
• https://www.mail-tester.com

The image above is from the last one on the list, which unfortunately will only let you test 3 emails within 24hr period for free.

[Deozaan]

Interesting that it says you have everything set up properly. Every email I've gotten from DC since the move has a big red warning saying that "this email has failed its domain's authentication requirements. It may be spoofed or improperly forwarded!"

[mouser]

[mouser]

Does it give you any clue about what it doesn't like?
If you view the email headers do you see anything that might give a clue?

[Deozaan]

Interesting that it says you have everything set up properly. Every email I've gotten from DC since the move has a big red warning saying that "this email has failed its domain's authentication requirements. It may be spoofed or improperly forwarded!"

Does it give you any clue about what it doesn't like?
If you view the email headers do you see anything that might give a clue?

Hmm... Come to think of it, this may be a result of me using an email forwarder.

But I do that for a lot of addresses and this is generally the only one I see these warnings about, which made me think it was a problem on your end.