how-to block ads
1) Open a command prompt. If you can't find the little sucker in Windows just hit "start", click on "run" and type cmd. If you are running Linux or a derivative, we'll just assume you already know how to run Telnet on a port other than 23.
2) In that command prompt "DOS box", type telnet mail.dslreports.com 25 which will result in one of two results:
a) NOT blocked:
If you get "a)", then your mail server or client has issues other than a port block by SBCIS. If you get "b)" and need to use servers other than what SBC provides, see »AT&T Midwest/Ameritech FAQ »Here's what to do if port 25 is blocked for you.