[Hugh R]

I keep getting this today. Haven't changed anything, tried lots of stuff on the google search, something about going from port 25 to 587, but no love. Anyone have any thoughts? I seem to receive OK, but can't send. Is says

"The message could not be sent because the server rejected the sender's e-mail address. The sender's e-mail address was 'hugh.rose@comcast.net'. Subject 'test', Account: 'mail.comcast.net', Server: 'smtp.comcast.net', Protocol: SMTP, Server Response: '530 Authentication required', Port: 25, Secure(SSL): No, Server Error: 530, Error Number: 0x800CCC78"