General :: No Incoming Comcast Email On Devices

I am having problem (same as original post at link below) with 3 comcast email addresses on android phone. Estimate started 9/25/13. Can send email, but do not receive when polling at 30 minute interval; also does not delete emails on server when deleted on phone to keep emails synced. I am using K9 email app. When checking incoming server settings, I get the following error message: "Setup could not finish finish. Username or password incorrect ()." I have not changed usernames or passwords.

POP3 server: mail.comcast.net
Security typre: SSL (always)
Authentication type PLAIN
Port: 995

Also tried deleting and re-adding account, and increased setting for folder size. (Was also having problem with deleted email addresses showing up in auto-fill lists -- only on web, not on android. That's been fixed with "slow sync" of address book. But then this new problem is even worse.) original post: No incoming e-mail on devices