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New Contributor

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3 Messages

Wed, Mar 31, 2021 2:25 PM

Emails to comcast.net addresses throttled

I run an email server behind a static IP address associated with a Comcast Business Internet account. This server has been running behind this address for over 6 years. When sending emails to comcast.net addresses lately, they are being delayed, and I'm seeing the following message returned from Comcast's server:

421 4.2.0 x.x.x.x throttled - try again later. please see http://postmaster.comcast.net/smtp-error-codes.php#rl000001

Where x.x.x.x is our static IP address.

Our SenderScore is 0.  We are a small business, and do not send any type of marketing emails. According to the link above, we should be able to send 1,200 messages per hour with a Sender Score of 0.  We don't even send that many emails in a month! This issues usually occurs when an email is sent to the same group of people, with around 4 having comcast.net addresses. Emails to comcast.net addresses are not sent every day, and may only be sent a few times per day.

We do not have any issues sending emails to any other domains, including yahoo.com, outlook.com and gmail.com, the issue is only with comcast.net addresses.

I suspect the issue is with the flawed Sender Score system. We have a low score because we don't have the volume of a large corporation, not because we send spam. We shouldn't be throttled for that reason!

I've called the Comcast Customer Security Assurance 4 times now, but they have not been very helpful.  Can anyone else from Comcast assist with getting our IP address whitelisted, so we can send emails to comcast.net addresses without an issue?

Thank you

Responses

Official Employee

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249 Messages

4 m ago

Hi! Thanks for reaching out over our forums page. I am sorry to learn about the issue you're experiencing with sending emails to https://comca.st/3m63KQa addresses. This is definitely not the experience we like to hear about. I can understand how important it is to be able to send emails without any issues for your business. We can certainly help. To research this further, would you mind sending us a private message with your name, address, and account number by clicking the "message" icon in the upper right page of any forum page? Once you click on that, input our shared handle Comcast Business to send us a private message.

New Contributor

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1 Message

2 m ago

We are having the same problem. We are trying to send just 5 emails and they just keep getting sent back to the email server with a message that the emails are being throttled. We normally probable send 20 emails to people at comcast.net a month. Can someone there please help. I have filled out the blacklist form but the answer is that we are NOT being blacklisted. Yet the emails sit in our queue with the throttled message. My email address is: tsg@cctg.com if you need to contact me directly. Thank you for your help.

Official Employee

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17 Messages

Thank you, @user_da1b61 for reaching out to us over our Business Forums. We would be more than happy to take a look at your account to see what may be causing this issue. Please send us a direct message. 

 

To send a "Peer to peer" / "Private chat message" message to "Comcast Business":

  • Click "Sign In" if necessary
  • Click the "Peer to peer chat" icon or https://comca.st/33Igi7Q
  • Click the "New message" (pencil and paper) icon
  • The "To:" line prompts you to "Type the name of a person". Instead, type "Comcast Business" there
  • - As you are typing a drop-down list appears. Select "Comcast Business" from that list
  • - An "Comcast Business" graphic replaces the "To:" line
  • Type your message in the text area near the bottom of the window
  • Press Enter to send it"

New Contributor

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3 Messages

2 m ago

Comcast has been no help with this issue, and it has not been resolved for me. Each time I called the Comcast Customer Security Assurance, the issue was supposed to be escalated, but I still have not heard back from anyone.

I had the same result with the blacklist form.

New Contributor

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3 Messages

2 m ago

I also sent a private message, as Gabe suggested, but that team seemed to be even less knowledgeable than the Comcast Customer Security Assurance. They said they were opening a case, but I never heard back on that case either.

Official Employee

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15 Messages

Hello @user_b8188e I'm so sorry to hear that no one has followed up on the case, but I can definitely take a look to see what's going on. Please send us a Live Chat with your first and last name as well as your service address so we can assist. 
 
To send a Live Chat, click the Peer to Peer chat icon at the top right of the page and enter Xfinity Support in the "To" section of the chat.