Gary-
Thanks for the info. I changed the port to 465 but I it didn't help. I think it'is probably because I contacted comcast for help twice and, after they were finished changing a lot of set up stuff, my set up is screwed up and I can't get it back to where it was... When I contacted them a third time, they advised me to use comcast internet for email. I did that and find it unacceptable.
