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Comcast Blacklisted email server


Comcast Blacklisted email server

This started with me trying to resolve an issue with one of my clients no longer receiving my emails. I use Outlook as my mail program so as per customer support to track down any email problem I had to  log-in into Comcast's webmail interface and send myself a test email. I did that and what I received was a bounced email notice with the following message from mailer-daemon@comcast.net.


This is an automatically generated Delivery Status Notification.     
Delivery to the following recipients was aborted after 2 second(s):

  * webmaster@xxxxxxxx.com"

There was also an attachment titled ATT00445.dat, below is what is in that attachment.


"Reporting-MTA: dns; resqmta-po-11v.sys.comcast.net []
Received-From-MTA: dns; resomta-po-07v.sys.comcast.net []
Arrival-Date: Thu, 16 Jul 2015 23:56:33 +0000

Final-recipient: rfc822; webmaster@xxxxxxxx.com
Action: failed
Status: 5.1.1
Diagnostic-Code: smtp; 550 Sender IP ( is blacklisted at ix.dnsbl.manitu.net
Last-attempt-Date: Thu, 16 Jul 2015 23:56:35 +0000"

So I called customer support again and reported the blacklisting, it was assigned a ticket and I was promised a call back within 24 hours. No call back after 48 hours so I called again and was told that the ticked had been closed that the problem was not Comcast but the receiving email account.

I said that It can not be the receiving email account because it never got that far, that the sending IP was blacklisted as per the attachment from comcast. The rep said that it didn't matter the icket was resolved and closed. After talking to three different support peopel, the last one being a supervisor. He told me that resetting all my comcast email accounts including the passwords would resolve the issue, I said that resetting all my comcast emails would not address the issue of the blacklisted mail server. He finally gave in and opened another ticket and that I would be contacted within 24 hours.


I have checked and the listed sending IP ( is in fact blacklisted  at mxtoolbox.com and the same IP whois lookup shows the owner as Comcast IP Services, L.L.C. Yet Comcast refuses to address this issue.


I came here in hopes that someone would help me convince Comcast to resolve the blacklisted mail serve.


Re: Comcast Blacklisted email server

Another 24 hours passed and still no call back from Comcast, so I call them again. The tech support rep I spoke to read from the notes on my latest ticket and I quote "when the customer calls again give him the following phone number to the Customer Security Assurance Department 1-888-565-4329." 


So I called this phone number and spoke to an agent that actually understood the issue of their blacklisted mail server. However he could not resolve the blacklisting he would have to elevate the issue to the next level. The next person I talked to ask me to forward the bounced email to her. She then proceeded to tell me the problem was the receiving email account that was causing the problem. I asked her to confirm the blacklisting of the listed sending IP and she confirmed that it was blacklisted and owned by Comcast. Yet she still insisted that it was the receiving email that caused the problem saying it was something I sent that caused their mail server to be blacklisted.

I gave up on trying to convince her that couldn’t be the case and just moved on to getting the listed IP removed from the blacklisting. I asked her to please request to have the IP removed from the blacklist and she said that I would have to make that request that she could not request to have Comcast’s IP be removed from any blacklisting and directed me to go to mxtoolbox.com and click on the Blacklists link. She told me to enter their IP and click the button. Sure enough the IP was blacklisted on three sites. She then told me to click on the first Detail button, close the popup and click on the link for Manual Removal.


That link took me to blacklist.lashback.com where she told me to put the IP in the DELIST REQUEST field and click the submit button. I told her that I was aware of lashback.com policy about one free request per month and that I felt it wrong that I should use my one free request to delist their IP and again she told me it was the only way, that she could not do it herself. She then said again “it’s the only way and that I would have to do the same thing for the other two sites that listed their IP as blacklisted and was there anything else I needed help with as this issue was considered resolved.”


I went ahead and finished the Delist Requist for the first listing as I saw it as the only way that blacklisted Comcast mail server would ever be delisted! When I went to the two other links for the blacklisted sites, neither one had a manual removal request process, of course by then I was no longer talking to the Customer Security Assurance rep.


So as of this writing the Comcast mail server with the IP of is still list on two blacklisting sites UCEPROTECTL1 and UCEPROTECTL2. http://mxtoolbox.com/SuperTool.aspx?action=blacklist%3a96.114.154.170&run=toolpage


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