Cannot email comcast.net from my private domain exchange email server
Cannot email comcast.net from my private domain exchange email server. This started recently.
Keep getting this reply:
Remote Server at comcast.net (2001:558:fd01:2bad::4) returned '400 4.4.7 Message delayed'
11/4/2022 3:27:27 AM - Remote Server at comcast.net (2001:558:fd01:2bad::4) returned '451 4.4.0 Primary target IP address responded with: "554 resimta-a1p-087338.sys.comcast.net resimta-a1p-087338.sys.comcast.net xxx.xxx.xxx.xxx found on one or more DNSBLs, see http://postmaster.comcast.net/smtp-error-codes.php#BL000010." Attempted failover to alternate host, but that did not succeed. Either there are no alternate hosts, or delivery failed to all alternate hosts. The last endpoint attempted was 2001:558:fd01:2bad::4:25'
I have gone through the process of removing block on ip address at comcast.net and their reply is it is not being blocked. I am also not on any spam lists, have what seem to be correct spf, dmarc, dkim records for my domain. Thanks in advance.
I am a customer of comcast business class internet and have spent time with Tier II support on this issue.
A ptr record was added but that did not fix the issue. They said it needs to be fixed at the Xfinity end. I can't post question on their support board because I do not have Xfinity internet.
5 months ago
@user_cae7a3 Thank you for taking the time to reach out to us here on our Xfinity Forums. I can definitely take a look at the account. It sounds like we may need to get a ticket open though. Please send us a DM with your full name and address to Xfinity Support.
To send a direct message:
Click "Sign In" if necessary
Click the "Direct Message" icon or https://forums.xfinity.com/direct-messaging
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