Go Premium for a chance to win a PS4. Enter to Win


GMAIL e-mails not being delivered to COMCAST.NET e-mail addresses

Posted on 2014-03-31
Medium Priority
Last Modified: 2014-11-12
We have a Google Apps customer that recently began having issues with email being sent from them to comcast.net email addresses.  The messages leave their Gmail mailboxes and are received by comcast.net email servers but then just disappear into the ether.  No delivery, no bounce back.  Everything was working as expected until last week.

I've been researching this for a few hours and have come to the conclusion that this is likely an issue relating to the emails being seen as spam or coming from a spammy server.  So I decided to go to mxtoolbox.org and run a test against the domain.  The negative portion of the results are below...  

Anyone have any thoughts beyond contacting Google and Comcast (which I've already done).  So far the suggestions were: add an SPF record (done), add DKIM.  Any one seen this before and actually resolved it?  I know how to fix the Reverse DNS does not match SMTP Banner when I run the e-mail server, but no idea about how to handle it in GMail... or if it is even the issue.  Comcast certainly isn't being of any real help.

      dns      urdomain.org       SOA Serial Number Format is Invalid        More Info
      dns      urdomain.org       SOA Expire Value out of recommended range        More Info
      spf      urdomain.org       A Valid SPF Record was not found        More Info
      smtp      aspmx.l.google.com       Warning - Reverse DNS does not match SMTP Banner        More Info
      smtp      aspmx.l.google.com       5.569 seconds - Warning on Transaction Time        More Info
      smtp      alt1.aspmx.l.google.com       Warning - Reverse DNS does not match SMTP Banner        More Info
      smtp      alt1.aspmx.l.google.com       5.663 seconds - Warning on Transaction Time        More Info
      smtp      alt2.aspmx.l.google.com       Warning - Reverse DNS does not match SMTP Banner        More Info
      smtp      alt2.aspmx.l.google.com       5.710 seconds - Warning on Transaction Time        More Info
      smtp      aspmx2.googlemail.com       Warning - Reverse DNS does not match SMTP Banner        More Info
      smtp      aspmx2.googlemail.com       5.632 seconds - Warning on Transaction Time        More Info
      smtp      aspmx3.googlemail.com       Warning - Reverse DNS does not match SMTP Banner        More Info
      smtp      aspmx3.googlemail.com       5.772 seconds - Warning on Transaction Time        More Info
Question by:ParadiseITS
  • 4
  • 3

Author Comment

ID: 39967150
As a test, I sent an e-mail from our account through my personal Xeams SPAM filter and it marked it as a 98% probability of being SPAM based on Bayesian... I just don't know exactly why or what to do about it.

Expert Comment

ID: 39967170
spf      urdomain.org       A Valid SPF Record was not found

I would start by adding the SPF record to the domain that is using Google Apps.


EDIT:  just reread the question and saw that you added the SPF record, but your results don't seem to reflect that....I would double check the DNS settings for the domain

Author Comment

ID: 39967248
I did do that -- I ran the test before I added the SPF record.
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!


Expert Comment

ID: 39967260
hmmm....I have Google Apps and I get the same reverse dns warning you are getting above.

Have you ran the domain through the blacklist check at mxtoolbox?

Author Comment

ID: 39967296
Yes, we have run it through all the tools at MXTookBox -- no blacklists.

Expert Comment

ID: 39967465
Do the emails have a signature?

Only reason I ask is because I had a customer whose ISP randomly started blocking their email due to their signature.

Author Comment

ID: 39967479
Yes and no -- we've tried it both ways.  At this point, nothing is getting delivered at Comcast.
LVL 15

Accepted Solution

Allen Falcon earned 2000 total points
ID: 39969069

Comcast has flagged your domain as a source of spam.

First and foremost, you need to scan every system in your domain to ensure you have no malware anywhere.  

Here are 7 steps that have proven successful in getting off blacklists from Google Apps domains:

1) Make sure your domain is really clean and that you are NOT using tiny URLs in your emails (body or footer). Also, make sure you are following ALL of Google's Bulk Senders Guidelines.

2) Make sure your SPF records are clean and correct (make sure you include ANY source of email); If you make SPF corrections, you need to wait 24-48 hours for them to propagate before continuing on. Please note that your SPF should end in "~all", not "-all" or other options. The "~all" suffix appears to make a difference.

3) THEN submit this form to Google. Google does not say how long any action will take. You can try to continue the process after about 24 hours, but you may need to wait 48-72 hours or longer.

4) Test emails to @gmail.com addresses and to addresses running Google Apps for Business/Education
-- the latter should get through first
-- have the recipient mark the message as "Not Spam" if it ends up in the Spam folder

5) If you do not have an @gmail.com account to work with, create one

6) Log into the @gmail.com account, go into settings and Accounts

Setup a "Send mail as" connection to the email address from which you cannot send to gmail addresses (source address)
The source address will receive a confirmation/verification message ...click the link to approve and complete the process
You can now log into your @gmail.com address and send as if you are sending from the source address

7) From you @gmail.com address, send as the source address and send a message to the @gmail.com address

Yes, you are sort of sending a message to yourself
Make sure the message has a subject line and some text in the body
When it arrives back at your @gmail.com account, it will likely end up in:spam.
Find the message and mark it as "Not Spam", this action tells gmail that the sender is not spamming -- and is valid

Featured Post

Fill in the form and get your FREE NFR key NOW!

Veeam is happy to provide a FREE NFR server license to certified engineers, trainers, and bloggers.  It allows for the non‑production use of Veeam Agent for Microsoft Windows. This license is valid for five workstations and two servers.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

When you’re making plans to join the modern business race, you should analyze various details that may affect your results. Nowadays, millions of businesses are trying to grow into established and appreciated professional enterprises.
One-stop solution for Exchange Administrators to address all MS Exchange Server issues, which is known by the name of Stellar Exchange Toolkit.
Along with being a a promotional video for my three-day Annielytics Dashboard Seminor, this Micro Tutorial is an intro to Google Analytics API data.
This Micro Tutorial will demonstrate importing calendar invites from events such as webinars into your Google Calendar.
Suggested Courses

877 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question