Emails not being being delivered

[ranwaldo@comcast.net]

Invoices and other emails from WHMCS are not being delivered to customers on Comcast email servers. I am not getting a bounce message, the emails are just vanishing.

 

I have reproducible test cases using email addresses on my Comcast account.

(1) Sending to a Comcast email address with the default settings, the emails are sent by WHMCS but never received.

(2) On another Comcast email address, I have modified the settings in comcast.net to set 'Spam Filter = Off'. Messages to this address are delivered fine.

 

Conclusion: the Comcast Spam Filter is discarding the messages.

 

I have tried, without success, to get Comcast Customer Support to help me resolve the issue. I finally have a ticket number and am waiting for their level 2 to contact me. I don't don't think it would be reasonable for me to have to tell all of my customers they must turn off Comcast Spam Filtering.

 

Has anyone else experienced a similar problem, or have any advice for me to resolve it?

 

Thanks, ~Randy

[WHMCS John]

Hi,

I'm not aware of any other reports from other users at present. Whilst you wait to hear back from Comcast on the issue, here is some general advice about avoiding your emails being mistakenly marked as spam:

 

As all IP addresses have been recycled or reused, it is possible that at some point in time your mail server IP address may have had a bad reputation, or if your mail server is in a shared hosting environment(or similar to one) other users mail habits can affect your reputation as well.

 

 

1.Try using SMTP rather than PHP Mail under Setup >> General Settings >> Mail Tab. Many email providers block PHP mailer scripts as "unverified mail".

 

2.Verify the email address you are sending "from" has actually been created on your server, and can send/receive mail normally.

 

3.Check your mail servers IP to verify it is not listed in any black lists at http://mxtoolbox.com

 

4.Contact your web hosting or mail server provider for investigation into your IP reputation. They will be able to contact other email providers on your behalf.

 

5.If it is suspected that the wording of an email being sent by WHMCS may be triggering a filter, try customizing you email templates so they do not appear exactly like every other WHMCS installations emails.

 

6.Verify your domain has an accurate and strict SPF record setup, as well as a correct PTR record.