Error message when I try to send email:

You either don't have the correct outgoing mail server (SMTP server) name or you are trying to connect to your own ISP's SMTP server through while connecting to a different ISP's mail server.

 

Steve 

Evidently Comcast has changed the name of their SMTP server.  Only they (Comcast) will know so call their Customer Support as their online documentation may not be up to date.

I like where Steve is going. Make sure you are on the Comcast network or you won't be able to use their SMTP server. You may also have port 25 blocked. If you are on the Comcast network directly (no router), and still get this message then contact customer support to see if they are blocking port 25. If they are there is a work around that they have.

 

P.S. They have not changed their server names.

 

P.S.S. I just noticed a possible typo in the original message. If the server name in your settings is SMPT.comcast.net that will cause your issue. It should be SMTP.comcast.net. Make sure the name is spelled correctly in Tools -> Accounts -> Servers -> Properties -> Servers Tab