Can port 25 be used for SSL-enable SMTP server ?
843830Aug 13 2007 — edited Aug 13 2007Hi,
Our customer is using port 25 for a SSL-enabled SMTP server without certificate. When our email client tried to connect to it, the following exception thrown:
DEBUG SMTP: exception reading response: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?
Since we don't want to ask our customer to change their port configuration unless absolutely necessary, we did some tests with our own SSL-enabled SMTP server that uses certificate. Here is what I got:
1) with port 25, got the same exception as above;
2) with port 465, worked fine;
3) with any other randomly pick up valid port, worked fine.
This made me wonder if 25 is for non SSL SMTP server ONLY. By the way, I'm using Javamail 1.3.4 and JSDK 1.4.2_02. My question is whether we can configure javamail so that port 25 can be used by SSL-enabled SMTP server?
Your help will be appreciated.