Hello, javax.mail.MessagingException: Unknown SMTP host:

Question

Hello,
I am trying to send a mail and use a smtp Server which is located on the internet. I am however behind a firewall and am getting the following exception being thrown:
javax.mail.MessagingException: Unknown SMTP host:
This implies that I need to provide some settings for my proxy server. I though to solve this problem I could do the following:
System.getProperties().put("proxySet", "true");
System.getProperties().put("http.proxyHost", proxyHost);
System.getProperties().put("http.proxyPort", proxyport);
This however does not solve me problem as I still get the above exception. Could someone please give help me. Any suggestions,solutions or ideas as to what the problem might be would be appreciated.
Thanks much,
Alex.

Answer 1

HTTP is not SMTP.
Your proxy server no doubt allows your system to send
HTTP traffic to and from the outside world, and using
that code you posted would allow Java classes to do
that as well. But HTTP is not SMTP. Ask the network
people who configured your proxy server if it can act
as an SMTP proxy, and if so what you have to do to
use it in that way.Thanks much for your reply. I am however a little confused. Could you explain to me exactly what an SMTP proxy is/does.
Thanks much,
Alex.