johnho3636's profile

Visitor

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10 Messages

Tuesday, January 23rd, 2024 8:40 PM

Emails not received to Comcast addresses in mass distro list

We are having issues receiving emails from our kids' school district when part of a mass email to many parents. It seems to be timing out with the following error:

1/23/2024, 11:10 AM | Defer | Reason: [{LED=451 4.2.0 Throttled - https://postmaster.comcast.net/#RL000010};{MSG=};{FQDN=mx2.mxge.comcast.net};{IP=2001:558:fd02:243f::3};{LRT=1/23/2024 4:10:37 PM}]. OutboundProxyTargetIP: 2001:558:fd02:243f::3. OutboundProxyTargetHostName: mx2.mxge.comcast.net

 

1/23/2024, 11:26 AM | Fail | Reason: [{LED=550 5.4.300 Message expired -> 421 4.4.2 Connection dropped due to SocketError};{MSG=};{FQDN=mx2.mxge.comcast.net};{IP=2001:558:fd02:243f::3};{LRT=1/23/2024 4:26:21 PM}]. OutboundProxyTargetIP: 2001:558:fd02:243f::3. OutboundProxyTargetHostName: mx2.mxge.comcast.net

The district claims it's not a problem on their end. Anyone have this happen or is there a Comcast staff member that can help?

3 Messages

6 months ago

I am having issues receiving certain emails too.  This started the beginning of the month/year.  I receive some emails but not all especially from a mass distribution sender.  Also cannot receive emails from my bank when trying to complete multi layer authentication to access account.  I've always received them previously.  Called Comcast today but after 1 1/2 hours of frustration all they did was have me sign out totally from my Xfinity account and it didn't help.  I heard from a personal friend that she was not receiving any emails to her comcast account either.  Anyone else having this issue?

1 Message

6 months ago

Yes! I am having this exact same problem with mass emails I send for my committee. All the receivers that are @comcast.net are not receiving due to that same Throttle error message. I tried reducing the number of emails sent to 15 and still having the issue. My tech tried slowing down the send rate, but it did not help for these comcast emails. This just started happening recently. Help!!!!

Problem Solver

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1.3K Messages

@user_s4f4zh Hi there, very sorry about the email trouble. Are you using the email portal or a third party tool? 

I no longer work for Comcast.

Contributor

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14 Messages

6 months ago

I am having the same issue. I have a mass distribution list (less than thirty names) for my work and on three occasions only recipients with comcast emails are being bounced though I do not get notified until days later. Even adding myself to the list with my personal comcast account had the same result. The error is:

Your message couldn't be delivered. Despite repeated attempts to contact the recipient's email system it didn't respond.

Contact the recipient by some other means (by phone, for example) and ask them to tell their email admin that it appears that their email system isn't accepting connection requests from your email system. Give them the error details shown below. It's likely that the recipient's email admin is the only one who can fix this problem.

For more information and tips to fix this issue see this article: https://go.microsoft.com/fwlink/?LinkId=389361.

Official Employee

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1K Messages

6 months ago

@johnho3636

 

Hello this link https://www.xfinity.com/support/articles/spam-filters-and-email-blocking-new-experience has great information on checking your spam filers  as well as this link for sending to xfinity  

https://spa.xfinity.com/postmaster?faq=avoid-blocks-ipv4

 

Visitor

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10 Messages

https://forums.xfinity.com/conversations/email/emails-not-received-to-comcast-addresses-in-mass-distro-list/65b0242c22d9f633de7f5add

Please take a look at this post and see if you or someone else can help. This is not about personal spam filters. This is a Comcast email issue. Thanks!

Visitor

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10 Messages

6 months ago

I posted in a forum with an issue and was hoping a Comcast monitored these and offered help. Does this happen? Can an employee respond here and can I point you to my original post that I and a lot of other email users need help with?

Note: This comment was created from a merged conversation originally titled Do Xfinity engineers/CSR's monitor the forums?

Official Employee

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1K Messages

@johnho3636

 

Hello this link https://www.xfinity.com/support/articles/spam-filters-and-email-blocking-new-experience has great information on checking your spam filers  as well as this link for sending to xfinity  

https://spa.xfinity.com/postmaster?faq=avoid-blocks-ipv4

 

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Visitor

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10 Messages

https://forums.xfinity.com/conversations/email/emails-not-received-to-comcast-addresses-in-mass-distro-list/65b0242c22d9f633de7f5add

Please take a look at this post and see if you or someone else can help. This is not about personal spam filters. This is a Comcast email issue. Thanks!

Official Employee

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1K Messages

@johnho3636

I did see the post the 2nd link gives information on how to avoid blocks when sending to Comcast.   Lets take deeper look into your account as well

Could you please send our team a direct message with your full name and full address? Our team can most definitely take a further look at this issue.

 

To send a "Direct Message" to Xfinity Support:

 

Click "Sign In" if necessary

 

Click the "Direct Messaging" icon or https://comca.st/3EqVMu7

 

Click the "New message" (pencil and paper) icon

 

The "To:" line prompts you to "Type the name of a person". Instead, type "Xfinity Support" there

 

- As you are typing a drop-down list appears. Select "Xfinity Support" from that list

 

- An "Xfinity Support" graphic replaces the "To:" line

 

Type your message in the text area near the bottom of the window

 

Press Enter to send it

 

 

 

 

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Visitor

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10 Messages

Unfortunately this isn't as simple as getting blocked. This is a timeout situation where Comcast emails aren't getting through to the Comcast email server for some reason. It's happening to multiple Comcast customers and all of a sudden started happening within the last few weeks. I've sent a DM to Xfinity Support so hopefully someone can help.

3 Messages

6 months ago

To the Support staff at Comcast/Xfinity, this is not a spam filter issue. I don’t think you understand what our issues are. All of a sudden, we have stopped receiving emails sent by small or large companies/businesses or individuals. They are apparently being blocked by Xfinity to our email Inboxes. We need technical assistance with this issue immediately.

Official Employee

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1.2K Messages

Thank you for taking the time to reach out and being part of the Xfinity family, user_6uojju. That's definitely not the experience we want you to have. I'd also be frustrated if I stopped getting emails from larges businesses. You've definitely come to the right place to get this taken care of. In order to get started can you please send me a private message to Xfinity Support with your full name and full address by clicking the chat icon in the top right?

 

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Gold Problem Solver

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25.7K Messages

6 months ago

... 1/23/2024, 11:10 AM | Defer | Reason: [{LED=451 4.2.0 Throttled ...

You need help from a grownup. Let's see if @XfinityAlex has a minute or two to spare . . .

Please be aware that there are 2 kinds of responses in this Forum: Replies and Comments. When you Comment on a post by scrolling down to "Comment on this post here...", I am notified of your response. But if you select Reply, I am NOT notified and may not be aware of your response.

Official Employee

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840 Messages

For RL000010, if you're having issues, the domain is the sender will be needed to help diagnose.  I'll file a ticket to get that put into the SMTP/bounce response so it's easier to obtain.  Happy to help here, just need a bit of information.

Official Employee

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840 Messages

6 months ago

@johnho3636 Could you share the sending domain or IP address? The domain is more relevant here, but either could help.

Visitor

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10 Messages

Yes... boyertownasd.org

Contributor

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14 Messages

6 months ago

This is happening to multiple people and businesses in the past month… not to one person or domain… it is Comcast that has the issue. In my case my domain is CranberryCatholic.org. And the issue is distribution list being blocked or timing out at Comcast end. Individual emails go out okay.

Official Employee

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840 Messages

@hollyberry​ It's not specific to your organization.  I've made an adjustment on our end (for everyone), and I believe that should help organizations such as yours.  Please let me know if you're still seeing an issue.

Visitor

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10 Messages

6 months ago

Adding my domain as a comment in case XFinityAlex doesn't see the reply!

boyertownasd.org

Official Employee

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840 Messages

@johnho3636​ I found yours, and I think the change I made (noted above) should help with your issue.

Visitor

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10 Messages

Thanks Alex! I've asked the district to follow up with me after their next mass email so I'll let you know soon if it works!

1 Message

@XfinityAlex Can you check to see if lawrencebgc.com was affected as well. Thank you...

Official Employee

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840 Messages

@user_w9kzlz It appears to have been similarly impacted, but looks okay over the past few days.

Visitor

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4 Messages

Can you please (please!!???) check aldersgatede.org.  I would very  much appreciate it!

1 Message

6 months ago

I have been managing email servers for a few organizations over the last 20 years.  I find it hard to believe that so many people sending to comcast.net recipients have their own email servers configured incorrectly.  The mass public did not suddenly enter bad settings onto their email servers to cause email only to comcast.net to not be delivered correctly.  Comcast recently changed something with their email processing - not the rest of the world.  However, the sampling of the mass public having this issue could all be doing the same thing - sending out mass emails.  The users in this thread are churches, non-profits, school districts, and others whose mass email recipients are going to be large lists of personal email addresses, not work email addresses, so there will be lots of comcast.net destinations in the email blasts.

My example below is for a bounce that went to 32 comcast.net recipients.  The number of recipients may be the issue.  A possible workaround is to instead send to smaller chunks of recipients, see if using BCC will get emails through, or use products designed for mass emails, such as SalesForce.com or ConstantContact.

@XfinityAlex - are you able to disclose exactly what change you made a day or two ago, or at least the nature of the change, that you believe may have helped?

---------------------------------------------------------------------------------------------------------------------------


For those using MS365 to send email, bounce messages look like this:

(One of these appears in the NDR for each recipient.)

Later in the email is a compilation of diagnostics that administrators look at to determine the cause.  It is apparent that the root cause is on Comcast's end.  However, with Comcast not yet telling us why this is happening (such as too many recipients) the blame could be on the sender.  

Official Employee

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840 Messages

@user_kq4wuc​ The items you're showing above are different.  I've reached out to Microsoft (still waiting on a response).  The items above were related to domain reputation and spikes in volume.  Yours is different, and a socket error suggests that there's either a timeout being reached, or some error in communication.  I need Microsoft to respond what they're seeing on their side of things as we haven't changed anything in that area in quite a while.  I also reached out to Google (we also get a huge amount from Google over IPv6), and while they initially responded, they're still looking into their data.  I'll see if I can get a follow-up from both of them later today.

Visitor

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4 Messages

6 months ago

We at aldersgatede.org are having the same issue.  The e-mails we send to @comcast.net addresses are failing with the same error.  This has been going on since early December 2023.

Official Employee

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840 Messages

@wweldin​ I made a change last week, and it looks like it had a positive impact on your messages.  Let me know if you're still seeing the issue as the week progresses.

Official Employee

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1.1K Messages

Hey @wweldin,

 

Thank you for letting us know of your issue here on our official Xfinity Community Forums support page. Thanks for the assist @XfinityAlex! We just wanted to follow up and see if you are still experiencing issues with sending emails to the Comcast.net domain. Please let us know at your next available convenience.

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Visitor

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4 Messages

@XfinityAlex​ Alex thank you SO VERY MUCH!!!  We sent out a mailing today and all the @comcast.net mails went through.  Really hope you know how much we appreciate your fixing this!!!   Peace be with you.

Official Employee

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1.1K Messages

I am so glad to hear that everything is working as intended now! If there happens to be anything more my team and I could assist you with, please let us know!  

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Visitor

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4 Messages

6 months ago

I am having this same issue at...aldersgatede.org.  Whenever we send a group email, nothing goes through to any of the @comcast.net emails although other e-mail services receive and process the email just fine.  I sent a long time on the phonetoday  trying to find someone in Comcast to help me with this  only to be told to report the issue via spa.xfinity.com (again).  I'm sure hoping Alex can help us!!!

3 Messages

6 months ago

@XfinityAlex 

PLEASE HELP!

My company is suddently having this same exact issue when trying to send a weekly volunteer email! The email gets sent/delivered fine to all recipients EXCEPT the comcast.net email addresses (~30 or so in the list).

ERROR: https://postmaster.comcast.net/#RL000010};[{LED=451 4.2.0 Throttled - 

Our MSP is zero help and we don't know where else to turn to get this fixed! 

communityfoodshare.org

This is so frustrating and I do NOT want to spend one minute of my precious time on the phone with some support person that is not going to have a clue what I am talking about (I treasure what few brain cells I have left)!

THANK YOU!!!!

Official Employee

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840 Messages

@kjp817​ We made a change last week to that mechanism, and I don't see that it has impacted your domain since then.  Can you confirm that it looks good over the past 3-4 days? 

3 Messages

@XfinityAlex We still had the exact same issue with the weekly emails sent on Thursday 1/25/2024. Is that before or after your 3-4 day reference above?

We would be sending another either Weds or Thurs of this week, but we are nervous to keep sending these because we don't want our domain to get put onto some blacklist by Comcast or anyone else.  Should we continue with the email this week and hope for the best?

How do we know if the change you mention affects us?

Sorry if I seem cynical.

(edited)

6 Messages

6 months ago

@XfinityAlex can you please help me as well. I've been dealing with this for months and have called into the assurance team multiple times but can't get any help. Our company is having the same issue as everyone above, our domain is genecooksupports.org 

Can you please help? 

This is the message we get, the e-mails get throttled then eventually time out. It happens anyone that sends from genecooksupports.org to an @comcast user.

Reason: [{LED=451 4.2.0 Throttled - https://postmaster.comcast.net/smtp-error-codes.php#RL000010};{MSG=};{FQDN=2001:558:fd02:243f::3};{IP=2001:558:fd02:243f::3};{LRT=1/31/2024 2:26:16 PM}]. OutboundProxyTargetIP: 2001:558:fd02:243f::3.

Official Employee

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840 Messages

@user_le9b5a​ I made an adjustment or two, please let me know if you're still seeing the issue.

6 Messages

@XfinityAlex​ Thank you!!

Once the employee who sends out the e-mails to that groups sends another one out I will let you know the results!

Official Employee

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1.2K Messages

Hi there @user_le9b5a. I am sorry to hear you are having troubles with you email. You are in the right place ane we are happy to assist you today.

Please send us a direct chat message with your full name and complete service address to “Xfinity Support”. To do so, click on the chat icon located at the top right of this forums page.

Here's the detailed steps to direct message us:

  • Click "Sign In" if necessary
  • Click the "Direct Message” icon (upper right corner of this page)
  • Click the "New message" (pencil and paper) icon
  • Type "Xfinity Support" in the to line and select "Xfinity Support" from the drop-down list
  • Type your message in the text area near the bottom of the window
  • Press Enter to send your message

 

Let me know if you have any questions.

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

6 Messages

@XfinityAlex​ Thank you, it is working now!!!

Official Employee

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888 Messages

@user_le9b5a  Thanks for following up with us. This is great news! Glad to know everything is resolved for you. If you need anything more please don't hesitate to reach out! 

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick
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