MacOS Apple Mail not connecting to my Comcast email account

 7/18/2024 I should have mentioned that I have been getting email coming through yesterday morning, but still have the error message for blacklisted. I removed the @comcast.net from both imap & smtp and it accepted the change. I still get the error message. It disappears for a while and then comes back, strange. If I go to >mailbox>get new mail the error will go away, but pops back up after a minute or two. At any rate, again thank for your help. If there is anything else you think of for me to try, I would be glad to, but I’m ready to move on. I can get the email directly from comcast on their website. Thank you.

I did add @comcast.net back to the user names for both imap & smtp.

7/19/2024 Everything is working this morning. Mail is flowing and no blacklist error. Good luck to everyone.

I am sure you are aware that Comcast has terrible customer service and getting a resolution through them is next to impossible. I do believe that it is Comcast that is blocking access to their services since your IP Address is not one of theirs. They do claim that you can continue using the email address when using another Internet Provider, but it is something that they control.

https://www.xfinity.com/support/articles/using-email-only

What results do you get when you go to Mail > Window > Connection Doctor?

Can you send/receive email using their Web Portal?

To verify the settings in the Mail App:

Incoming Mail Server (IMAP)

• Uncheck the Automatically Manage Connection Settings
• The Port should be 993
• Use TLS/SSL should be checked
• Authentication type should be Password

Outgoing Mail Server (SMTP)

• Under Account, does it say (Offline)?
• Uncheck the Automatically Manage Connection Settings
• The Port should be 587. You can also try 465 to see if that makes a difference.
• Use TLS/SSL should be checked
• Authentication type should be Password

I am sure you have tried this several times, but can only offer this:

• Enter your Password again at the Incoming Server Settings (IMAP)
• If the name entered at User Name ends with "@comcast.net", try removing that so it just has the first part of your email address and if it does not have the "@comcast.net" suffix, try adding it to the User Name.

I just started having the same problem on all my devices for two accounts. They work fine if I access Xfinity email directly through Safari or Google. I receive a similar message..The following alerts are from the IMAP server for “Becky”:Temporarily blacklisted IP Address - try again later.

Are you using the Xfinity router?

The IP Address you listed does not appear to be a Comcast IP Address. Are you using a static address to connect to the internet. Dynamic IP Addresses provided by Comcast should not be appearing on any blocklist as those normally only affect static IP addresses.

I assume you are also not running an email server on your computer?

To send a Comcast.net email address, it must go through the Comcast SMTP server.

The settings for your Comcast email will depend on if you are using a POP or IMAP account. For a POP account:

Go to Mail > Settings > [mail box] > Server Settings, and you should have the Incoming Mail Server (POP) Host Name showing mail.comcast.net and the Outgoing Hostname for the SMTP server should be smtp.comcast.net.

My router is from Lumos (ISP). I used to have comcast, but haven't used them for a couple of years. I just continued to use their email services. My mail settings are imap.comcast.net and smtp.comcast.net and nothing in the advance imap settings. This issue start like other peoples, mail stop getting messages and the alert indicated that the password was incorrect. I tried changing the password multiple time and then I started seeing the blacklist message. Comcast was no help, Lumos was no help everyone pointing fingers somewhere else. So, I don't know who to escalate a call to. I've also removed accounts and added them back, shut everything down, checked account settings on Xfinity's side, made sure the third party box for mail was set....clicked my heels, turned around 3 times.... :) Nothing works. Thanks for responding and trying to help. Any further ideas would be helpful.