CHECKING YOUR OUTGOING MAIL SERVER (IS PORT 25 BLOCKED?)
Type the following command:
telnet example.com 25
If Port 25 is not blocked, you will get a successful 220 response (text may
Connected to example.com.
Escape character is '^]'.
220 cl34.gs01.gridserver.com ESMTP Exim 4.63 Tue, 24 Jun 2008 13:45:04 -0700
If Port 25 is blocked, you will get a connection error or no response at all.
telnet: connect to address 220.127.116.11: Connection refused
telnet: Unable to connect to remote host