I am trying to change my Comcast email from POP to IMAP in WLM 2012.  I can receive mail but I am unable to send.  The port settings I have used are 465, 25 and 587 for the outgoing server SMTP.comcast.net.   Neither port setting works.  I have checked the box for a secure SSL connection.   I get server error number 550.   Does anyone know the correct port settings.  I called Comcast, but they said it was a WLM issue (surprise). I am on Windows 10.