How do I receive mail on Outlook 2007 from my Comcast.net account?

In the past, I’ve never had an issue receiving mail via Comcast in Outlook 2007. Two weeks ago I have not had any luck receiving any mail through outlook. I can access my Comcast mail through the Comcast server and by way of Ipod but not through the Outlook server. I have the problem on two separate computers. I have not had any success with speaking to the Comcast help desk. Thanks!