I am trying to add comcast email to Apple mail. What am I doing wrong?

@user_eb1770 

​I am trying to add a new comcast account to my Apple Mail acct. I keep getting the following:​

​Unable to verify account name or password.​

​I have restarted everything, more than once​

​I have changed my password.​

​I have verified that the comcast email works.​

​What is the problem?​

What are your settings?  Are you using the entire [Edited: "Personal Information"] address?

There's another issue with apple mail I found while looking at something else on my stuff.  Maybe you hit it too. You're talking to a Dovecot server when you connect to Xfinity.  There's a parameter called:

mail_max_userip_connections

It's set to 12 in the default config file.  I don't know what Xfinity sets, but apple mail tries a whole bunch of connection attempts when it sets up email.  You'll burn through at least 8 connections back-to-back hitting the server in rapid succession while it tries to "auto-configure" the connection, and various encryption schemes including cram-md5 (which won't work), and it does this while trying to guess the outbound SMTP server at the same time.  It's annoying, and I'd call it a misbehaving email client.  The mail app is even active regardless of if you even launch the app or not.

So if you've got another device on your network checking your email account (any xfinity account, phones, etc), you can hit this user max IP connection limit, and you end up in temporary authentication jail.  Shut off WiFi and Ethernet on everything that checks mail on Xfinity, delete your partial account setup that isn't working, wait 10-15 minutes or so to get out of authentication jail, and try to setup the email account again.  Then it may take your username and password.