Ronald, are you using the Mail application that comes with OS X?
If so, start up Mail, and then go into Mail's Preferences pane and make sure that all of your settings are correct. For Comcast, click on the Accounts tab and then:
Fill in the various fields, with your email address etc, Incoming Mail Server should be "mail.comcast.net", User Name - your Comcast user name, Password - your Comcast password, Outgoing Mail Server should be smtp.comcast.net
Then click on the advanced tab and make sure that the "enable this account" box is checked, along with the "include when automatically checking for new mail" if you have that particular option enabled. You should probably also have "remove copy from server after retrieving message" checked, if Mail is your primary email program. It isn't mine, so I don't have that checked. The rest should be filled in and you shouldn't change it.
That takes care of the Comcast account (if there isn't any account set up, or you want to set up additional Mail accounts, simply put your cursor in the "Accounts" window on the left side of the Accounts pane in the Mail preferences and then click on the "+" sign down at bottom of the pane. You'll get a new account to set up.
As for Hotmail, you can't log in directly to Hotmail using Mail. Mail only works with POP, IMAP, .Mac and Exchange (if configured as an IMAP server).
Make sure that there is no firewall blocking your email traffic. In the system preferences, make sure that the Firewall is turned off. You'll find it under "Sharing".
You can get Hotmail email using Mail by following these directions:
http://email.about.com/cs/macosxmailtips/q...qt/et042503.htm(I've never tried it though, so can't vouch for it)
