Port 25 blocking is widely used by some ISPs to easily resolve two "problems".
First, it is a means used to block spam. By not allowing mail to be sent through any non-ISP servers, it is thought that spammers are prevented, at least in theory, from se
nding out huge volumes of unauthorized junk email. The second, and more common use of port 25 blocking, is to prevent small, home-based businesses from using "residential"
accounts for commercial purposes, which are billed at substantially higher commercial rates than residential. Thus, certain "key" ports (port 25 for email, port 80 for web,
etc.) are prevented from working in both directions (i.e. you can surf OUT to port 80 for web pages but, no one can surf IN to your computer on port 80).
With Port 25 blocking, anyone logged in to an ISP access number will only be able to send mail through the that ISP's mail servers.
To tell for sure if your ISP does not permit you to use external SMTP servers, try to telnet to mail.vfemail.net
port 25. If you are able to get through, you should ideally see this:
$ telnet mail.vfemail.net 25
Trying 108.76.175.1..
connected to mail.vfemail.net (108.76.175.1).
Escape character is '^]'.
220 vfemail.net ESMTP
If you get some other error, we will need to see the error to provide a diagnosis.
Many ISP's including AT&T, Earthlink, Mindspring and MSN do not ALLOW OUTGOING SMTP. Here are the information links for the various ISPs we have work with:
SOLUTIONS:
If your ISP uses port 25 blocking, it is beyond our control to correct this situation. If your email client supports it, you might try using port 587 (smtp-submit) instead
of 25 to send email. You can also enable SSL, which will not only encrypt your username and password, but will also use port 465.
For faster resolution of this problem, please check your ISP's policy on this issue prior to contacting our support department.
Finally, as a last-resort, VFEmail provides SMTP/IMAP services over what are typically HTTP ports:
SMTP - alt.vfemail.net port 80 (SSL enabled)
IMAP - alt.vfemail.net port 443 (SSL enabled)
You will have to manually accept the certificate because the hostname will not match, but your communications are still encrypted.