Sending Emails Fail after Required Comcast Password Update = authentication rejected

Comcast required me to update my Comcast password for security reasons when trying to log in to their site on 12/5/2023.

It had to be done from the main account holder account and not from the individual sub-email accounts.

This was done for two accounts.

I also updated the passwords on the accounts in two email programs and ever since then I can not send emails and I get the error message "authentication rejected " from Mailbird. Thunderbird also will not send.

I have other sub-email accounts that I did not change the passwords on Comcast and they still send fine, so it is appears to be a problem related to changing the passwords on Comcast.

It's very annoying when things get broken when companies make changes.

Any ideas?