smtp.comcast.net keeps asking for password, will not send outgoing mail

Since yesterday, November 29, 2020, smtp.comcast.net will not send outgoing mail from my local e-mail client (Microsoft Outlook under Windows 10). It keeps asking for authentication, which it already has.

UPDATE: Problem solved. Turns out I was trying to send an e-mail from an older Outlook account that was using an older password.