Emails being throttled and eventually time out. Why is this happening and how to fix?

Our church uses Outlook thru GoDaddy. Each week we send out an email to our 135 members. Frequently, but not always, the nineteen comcast.net emails are returned. I submitted the IP Block form and am told our IP address is not being blocked.

Our DKIM, SPF, Mx, and DMARC records appear to be correct.

Reason: [{LED=451 4.2.0 Throttled - https://postmaster.comcast.net/smtp-error-codes.php#RL000010};{MSG=};{FQDN=96.102.18.147};{IP=96.102.18.147};{LRT=8/13/2026 2:13:03 PM}]. OutboundProxyTargetIP: 96.102.18.147.

Reason: [{LED=450 4.4.318 Connection was closed abruptly (SuspiciousRemoteServerError)};{MSG=};{FQDN=mx1.mxge.comcast.net};{IP=96.103.145.162};{LRT=8/13/2026 7:59:55 PM}]. OutboundProxyTargetIP: 96.103.145.162. OutboundProxyTargetHostName: mx1.mxge.comcast.net

I don't know why Comcast is blocking us, or throttling us, for nineteen emails.

Looking for help to resolve.

Thank you.

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XfinityJon

Official Employee

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1.8K Messages

28 days ago

Good evening Uuuuuu889263737 I can certainly understand the concern there. I will be happy to look into this further for you. Aside from the mentioned emails, are you experiencing issues with any other email domains?

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Uuuuuu889263737

Visitor

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4 Messages

no, this wasn't answered. there was question regarding "...are you experiencing issues with any other email domains" which I answered via email to XfinityJon . Have not seen a response to that email. I'll answer it here also - no, the only problems we have are with these 19 emails to Comcast.net addresses.

Is there something more I need to do to help get this resolved?

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23 days ago

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XfinityAmira

Official Employee

•

5K Messages

Let us further look into this for you on our end, Uuuuuu889263737. Please send us a Direct Message. Here are the detailed steps to direct message us:
• Click "Sign In" if necessary
• Click the "Direct Message” (upper right corner of this page)
• Click the “Start new conversation" (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

https://forums.xfinity.com/conversations/guidelines/how-to-direct-messaging-within-the-forum/697ba1e570934d009185c514

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21 days ago

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Uuuuuu889263737

Visitor

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4 Messages

Thank you. I created the direct message as you recommended.

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21 days ago

0

Email

Uuuuuu889263737

Emails being throttled and eventually time out. Why is this happening and how to fix?

XfinityJon

Uuuuuu889263737

XfinityAmira

Uuuuuu889263737

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