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?

Responses

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user_7cc85f

Visitor

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16 Messages

10 months ago

I have the same or very similar problem, which is definitely NOT A SPAM FILTER ISSUE!!!!!!!!!!! My painstakingly curated email filter settings, which were made out necessity due to terrible default spam filtering, have been working for over a decade with no issues. Then around January 25th, 2FA emails are suddenly a blacklisted domain. This isn't a simple nuisance problem. Anyways just adding this useless comment to get a bot to tell me to check my spam folder.

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user_efk7eo

1 Message

10 months ago

@XfinityAlex,

Hi Alex, we're having the same issue as most people in this thread, but now it seems to work every so often without any rhyme or reason on my end. We’re a nonprofit church that sends out daily inspirational quotes and updates to people that have requested us to do so. Our mailing list for comcast users is only ~15.

(edited)

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XfinityAlex

Official Employee

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881 Messages

@user_efk7eo If you haven't already, please send me a DM with the domain of the sending entity. I'll take a look. Click on my name, find the three dots, look for a "Send Message"

10 months ago

0

A

allinneal

1 Message

9 months ago

Hi @XfinityAlex We had a sudden, drastic rise in soft bounces to only our Comcast.net emails on our email list on 2/15, and researching it led me here! I don't see a direct messaging icon, I can't find the 3 dots or a "send message" in your profile, and when I go to https://forums.xfinity.com/direct-messaging it just automatically reroutes me to the main forums.xfinity.com page. How should I proceed? Thank you!

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XfinityTy

Official Employee

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376 Messages

Hello @allinneal! Thank you for reaching out to our team on Forums, and thank you for creating a public posts. Unsolicited Direct Messages to an Official Employee of the Xfinity Community Forum, is a violation of Forum Guidelines. Were you having trouble receiving emails, or sending emails?

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

9 months ago

0

XfinityAlex

Official Employee

•

881 Messages

@allinneal I've sent you a DM to get the details.

9 months ago

0

U

user_mvvgi1

1 Message

9 months ago

Hi @XfinityAlex We have thousands of Comcast users reporting similar issues and are seeing a spike in soft bounces and RL000010 errors. Are you able to assist us with diagnosing our myenotice.com sending domain? Thank you!

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XfinityAlex

Official Employee

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881 Messages

@user_mvvgi1 I see your DM. I'll respond there. We should be able to help.

9 months ago

0

S

starbuck33

1 Message

I am the president of our HOA and we set up an email account recently to communicate to the HOA members. I am having the same issue as described here. I sent an email to 133 recipients, 22 were bounced back and they are ALL @comcast.net email addresses with the exact same error messages. I would really not want to reach out individually to these folks to ask them to contact Comcast, if you have ever tried a Comcast customer service call you will understand. Our neighborhood also only has Comcast for broadband and over the years we have developed a healthy distrust of the normal customer service phone tree. I found this thread and I am hopeful that this can be resolved without having to ask the 22 individuals to sort it out.

Please help!!

Below are the error messages with the email addresses redacted (for privacy purposes):

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.

Diagnostic information for administrators:

Generating server: PH7PR12MB7891.namprd12.prod.outlook.com
Total retry attempts: 7

@comcast.net
Remote server returned '550 5.4.300 Message expired -> 451 4.2.0 Throttled - https://postmaster.comcast.net/smtp-error-codes.php#RL000010'

8 months ago

0

XfinityKrista

Official Employee

•

1.5K Messages

Hello @starbuck33, thank you for taking the time to reach out on social media. I understand your concern with the email, and I'd like the opportunity to check into that for you.

To access your account, will you please send us a direct message with your full name and complete service address to “Comcast Business”. 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

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

8 months ago

0

U

user_MM59b8

2 Messages

6 months ago

I seem to be having this problem as well. I'll try a DM.

0

BruceW

Gold Problem Solver

•

26K Messages

6 months ago

I seem to be having this problem as well. I'll try a DM.

Please be aware that using Direct Messaging before you have been asked to do so is considered a violation of the Forum Acceptable Use Policy. See https://forums.xfinity.com/conversations/guidelines/xfinity-forum-acceptable-use-policy/602d9c64c5375f08cd574236.

You are encouraged to first post a description of your question or problem without including any personal information. If personal information is needed you'll be asked to provide it in a private Direct Message.

Did you read https://postmaster.comcast.net/smtp-error-codes.php#RL000010? :

RL000010 :: Mail to Comcast is queued and I see RL000010 in my email logs. What does this mean?

Comcast has instituted rate limiting on all inbound email traffic. This step was taken to protect our customers and our email system from unwanted spam and malicious attacks. Any systems affected by this rate limit will receive a 4xx message (temp-fail) during the SMTP transaction. This message is designed to instruct the sending server to try again at a later time to deliver its email.

This rate limiting policy is based on historical volumes and quality of that domain's volume. This should apply to both DKIM and SPF.

New domains that are expected to send significant amounts of email to Comcast subscribers should start by sending low volumes of mail, increasing as time goes on. As your domain sends more email, and our systems receive positive feedback from users, its limit will increase daily.

If the rate-limit is impacting your ability to deliver email, shortening your server's delivery retry interval should resolve the issue.

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.

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user_MM59b8

2 Messages

@BruceW My apologies. I was mistakenly inferring from the previous comments that we were welcome to do so. I see that is not the case.

I am having this same difficulty with the same error when sending to distribution groups from my organization. I'd love someone to take a look if possible.

6 months ago

0

XfinityAlex

Official Employee

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881 Messages

@user_MM59b8 I'll DM you to get more information

6 months ago

XfinityJamesC

Official Employee

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1.7K Messages

Greetings, @user_MM59b8! Thanks so much for taking a moment out of your busy day to leave a post on our community forum. I'm sorry to hear you're having the same issues with your distribution groups, but you have definitely come to the right place for assistance.

If you could send our team a direct message with your full name, the name listed on the account (if different), and the service address associated with your account, I'd be more than happy to look into this for you.

To send a Direct Message, please click on the “Direct Message” icon in the top-right corner of the screen, next to the bell icon, click the "New message" (pencil and paper) icon, then type or select "Xfinity Support". Type your message in the text area near the bottom of the window and press Enter to send your message and initiate a live session.

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 months ago

0

user_cm4302

Visitor

•

4 Messages

6 months ago

Hi, my Non-profit Animal Welfare organization sends email messages to our community members with username@comcast.net accounts.

For years this worked flawlessly, but since mid-April we have seen a HUGE increase in non-deliverable due to "server busy" or other similar recipient errors.

I opened a call [Edited: "Personal Information"] but we have not seen improvements in delivery despite reducing # of recipients to <300 for each message.

Can you please help me?

Thank you!

Charles

(edited)

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XfinityAlex

Official Employee

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881 Messages

@user_cm4302 Please click on my name and send me a DM with some additional information. Domains and IPs are helpful if you have those. I'll be happy to take a look for you.

6 months ago

0

XfinityGabriel

Official Employee

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1.9K Messages

user_cm4302, Hi! Thank you for taking the time to post a message over Xfinity Forums. It is nice to meet you. I can see why this error can cause an inconvenience. Let's work together to get to the bottom of this. To start, I just have some basic questions, this will point me in the right direction to help troubleshoot. Are you using a Comcast email to send these messages?

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 months ago

0

U

user_cn07fu

2 Messages

Hello -- I work for an environmental nonprofit organization. I'm experiencing the same issue that others have described here. Our softbounce rate has gone through the roof, but only for Comcast email addresses on our opted in list of recipients. @XfinityAlex or other staff, could you please send me a DM or invite me to send one so that We can workout a solution. I'll add that our DMARC and SPF records are all set up. Thanks a million!

(edited)

5 months ago

0

user_cm4302

Visitor

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4 Messages

@XfinityAlex Hi Alex, it appears our problem has returned after <2 weeks. on 6/22 we sent 2500 and only 1800 were delivered with ~700 bouncing back with 4004 "other receiver error" and 3004 "Server too busy". can you please help me (again) or advise? .. thank you!

5 months ago

0

user_cm4302

Visitor

•

4 Messages

@XfinityAlex

Hi Alex, it appears our problem has returned after <2 weeks. on 6/22 we sent 2500 and only 1800 were delivered with ~700 bouncing back with 4004 "other receiver error" and 3004 "Server too busy". can you please help me (again) or advise? .. thank you!

5 months ago

0

J

jphilipsen05

1 Message

4 months ago

@XfinityAlex I just found this forum and I tried to dm you so I could send you domain info to check for us, but when I click on your domain it seems there is no way to DM you. What is the best way to get a message to you with the domain that is experiencing this same issue?

1

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XfinityAlex

Official Employee

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881 Messages

@jphilipsen05 I'll DM you. Just a moment

4 months ago

0

narcsinc

Visitor

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2 Messages

4 months ago

I am having the same problem. Only comcast is blocking my emails which are on a comcast ciruit.

7/29/2024 12:52:43 PM - Server at AHAC21.AHAC.local returned '550 5.4.300 Message expired -> 451 4.4.397 Error communicating with target host. -> 421 4.2.1 Unable to connect -> SocketError: Failed to connect. Winsock error code: 10065, Win32 error code: 10065'
7/29/2024 12:51:37 PM - Server at comcast.net (2001:558:fd01:2bad::3) returned '451 4.4.397 Error communicating with target host. -> 421 4.2.1 Unable to connect -> SocketError: Failed to connect. Winsock error code: 10065, Win32 error code: 10065'

7/29/2024 12:52:43 PM - Server at AHAC21.AHAC.local returned '550 5.4.300 Message expired -> 451 4.4.397 Error communicating with target host. -> 421 4.2.1 Unable to connect -> SocketError: Failed to connect. Winsock error code: 10065, Win32 error code: 10065'
7/29/2024 12:51:37 PM - Server at comcast.net (2001:558:fd01:2bad::3) returned '451 4.4.397 Error communicating with target host. -> 421 4.2.1 Unable to connect -> SocketError: Failed to connect. Winsock error code: 10065, Win32 error code: 10065'7/29/2024 12:52:43 PM - Server at AHAC21.AHAC.local returned '550 5.4.300 Message expired -> 451 4.4.397 Error communicating with target host. -> 421 4.2.1 Unable to connect -> SocketError: Failed to connect. Winsock error code: 10065, Win32 error code: 10065'
7/29/2024 12:51:37 PM - Server at comcast.net (2001:558:fd01:2bad::3) returned '451 4.4.397 Error communicating with target host. -> 421 4.2.1 Unable to connect -> SocketError: Failed to connect. Winsock error code: 10065, Win32 error code: 10065'

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XfinityAlex

Official Employee

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881 Messages

@narcsinc This looks like something different. Could you send me a DM with your domain/IP addresses, and I'll take a look.

4 months ago

0

narcsinc

Visitor

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2 Messages

My domain is AHAC.US.COM

3 months ago

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U

user_h3sj8c

2 Messages

4 months ago

I have a customer having this issue and I'm getting rather frustrated on who and how to contact Comcast support. I don't see a chat or direct message option. Our customer is sending an email to multiple Comcast addresses and getting

Remote server returned '550 5.4.300 Message expired -> 451 4.2.0 Throttled - https://postmaster.comcast.net/smtp-error-codes.php#RL000010'

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XfinityAlex

Official Employee

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881 Messages

@user_h3sj8c DM me, and please provide the sending domain. We'll take a look.

4 months ago

0

U

user_h3sj8c

2 Messages

Info provided via DM

4 months ago

0

XfinityJamesC

Official Employee

•

1.7K Messages

Greetings again, @user_h3sj8c! I was not able to locate any DMs from your user profile, unfortunately. Can you please try sending us a new one? Just in case, our good friend, @BruceW, created this excellent explanation for the DM process.

To send a private message to Xfinity Support from any Forum page:

Click "Sign In" (if necessary - there will be a visible prompt)
Click the "Direct Messaging" (square speech bubble) icon
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 will appear. Select "Xfinity Support" from that list.
An "Xfinity Support" graphic should replace the "To:" line
Type your message in the text area near the bottom of the window
Press Enter to send it

See https://comca.st/3kYXwkR for an example

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

4 months ago

0

U

user_c2us8w

2 Messages

3 months ago

i am having the same issues

Remote server returned '550 5.4.300 Message expired -> 451 4.2.0 Throttled - https://postmaster.comcast.net/smtp-error-codes.php#RL000010'

Domain

Mountclemensumc.org

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XfinityAlex

Official Employee

•

881 Messages

@user_c2us8w I made an adjustment for that domain, let me know if you're still seeing an issue.

2 months ago

XfinityMartyR

Official Employee

•

1.5K Messages

user_c2us8w Hello! Did the adjustment that @XfinityAlex made help your issue?

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

2 months ago

0

iainm

Visitor

•

2 Messages

2 months ago

@XfinityAlex I am having the same problem (451 4.2.0 Throttled ) with emails from our HOA domain youroverlook.info. Is there a generic fix you can post here please, or do they all need to be fixed case by case?

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XfinityAlex

Official Employee

•

881 Messages

@iainm I adjusted the reputation for that domain.

2 months ago

iainm

Visitor

•

2 Messages

That fixed it - thanks Alex

2 months ago

0

BruceW

Gold Problem Solver

•

26K Messages

2 months ago

Did you check the https://postmaster.comcast.net/smtp-error-codes.php#RL000010 link? It's probably the most helpful information you are likely to get:

Comcast has instituted rate limiting on all inbound email traffic. This step was taken to protect our customers and our email system from unwanted spam and malicious attacks. Any systems affected by this rate limit will receive a 4xx message (temp-fail) during the SMTP transaction. This message is designed to instruct the sending server to try again at a later time to deliver its email.

This rate limiting policy is based on historical volumes and quality of that domain's volume. This should apply to both DKIM and SPF.

New domains that are expected to send significant amounts of email to Comcast subscribers should start by sending low volumes of mail, increasing as time goes on. As your domain sends more email, and our systems receive positive feedback from users, its limit will increase daily.

If the rate-limit is impacting your ability to deliver email, shortening your server's delivery retry interval may resolve the issue. Please be mindful that these are reputation-based mechanisms, and there are many factors that can impact those reputations. If the sending entity has poor reputation, sending "faster" or "more", may be increasingly detrimental. Ensure that you've also evaluated engagement, list auditing, and other best practices.

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.

0

XfinityAlex

Official Employee

•

881 Messages

2 months ago

@johnho3636 Please send me a DM with the domain of the school district, I'll take a closer look.

0

U

user_ztk5ph

1 Message

2 months ago

@XfinityAlex, We are experiencing the same issue as everyone else. We send out automated emails to customers (invoices, statements etc.), but never advertising, and they aren't going through to people with comcast emails. Our tech support has spent quite a bit of time working on it for us, then he came across this thread and thought you could help. The emails would all be coming from millersrentall.com

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XfinityAlex

Official Employee

•

881 Messages

@user_ztk5ph You should be good to go. I'm going to send you a DM with some additional information. This is *not* the same as other situations.

2 months ago

0

XfinityKrista

Official Employee

•

1.5K Messages

Hello @user_ztk5ph, thank you for taking the time to reach out on social media. I understand your concern with the emails, and I'd like the opportunity to check into that for you.

To access your account, will you please send us a direct message with your full name and complete service address.

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

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

1 month ago

0

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johnho3636

Emails not received to Comcast addresses in mass distro list

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RL000010 :: Mail to Comcast is queued and I see RL000010 in my email logs. What does this mean?

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.

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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.

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