[RndTbl] Gmail problem sending from your own SMTP server

[Hartmut W Sager]

Gmail is sure piling up its problems like never before in my 8-10 years of
using it.  In addition to the other issues of the last two months, we now
have:

The recent intermittent Gmail problem in sending from your own SMTP server
(if you don't want your "send from" address at your own domain name to be
an "alias" of your Gmail address) has now become an "always happens"
problem.  Here's the failure message you get from Gmail:

Message not delivered
You're sending this from a different address or alias using the 'Send mail
as' feature. The settings for your 'Send mail as' account are misconfigured
or out of date. Check those settings and try resending.
TLS Negotiation failed, the certificate doesn't match the host.

After much experimenting and Internet research, I found the answer buried
in Gmail support forums - an answer from a smart user, not from Google.  In
my case, since I use Tucows/OpenSRS for my SMTP server, the chain is

smtp-1.marityme.com [cname]
--> smtp.marityme.com.cust.a.hostedemail.com
--> 216.40.42.5 --> [RDNS] mail.hostedemail.com

Tucows/OpenSRS specifies the server *smtp.marityme.com.cust.a.hostedemail.com
<http://smtp.marityme.com.cust.a.hostedemail.com>*, which I cname to for
concenience and elegance, and that resolves to * 216.40.42.5*, whose RDNS
lookup gives *mail.hostedemail.com <http://mail.hostedemail.com>*.  Now,
unlike before, Gmail expects me to give *mail.hostedemail.com
<http://mail.hostedemail.com>* as the SMTP server in the "send from"
configuration, and then the sending mechanism works again (at least
yesterday and today, who knows about tomorrow).

The purpose of this post is to save other members days of headache trying
to figure this one out.

Hartmut W Sager - Tel +1-204-339-8331
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