QUOTE:
you do nothing wrong, I have been having the same (did not really needed it) but tested it and whatever you do: it want send .....
bug ?
Most likely not. A lot of ISP's block SMTP traffic from their users and generally with good reason.
SMTP is a mail transfer protocol designed to move mail between servers. It isn't intended to send mail from a server to a client. For example, Outlook doesn't use SMTP to transfer mail. The reason for this is that SMTP doesn't have authentication built into it. It was designed with the idea that all servers could be trusted to be who they say they are. And it's old enough that it predates spam as an issue.
The problem with from the ISP perspective is two fold:
1. Spam. If a user's computer gets taken over, it can start spewing out spam in bulk. A number of major ISP's started banning port 25 traffic and there was a noticeable drop in spam.
2. Money. End users generally shouldn't be hosting e-mail servers. They are notoriously hard to configure correctly and safely. Failure to do so generates technical support calls. Also, users using e-mail servers tend to use a lot more bandwidth then the average home user. So ISP's want those users on more expensive business class plans.
So what can you do about it? Most likely...nothing. A call to your ISP will generate the following response. "Sir, we do not block any ports." This isn't true. But they aren't going to change it for you. Eventually you may get to level 2 support who admits they do block that port. And they still aren't going to do anything about it.
Upgrading your package from your ISP can help but it can also be very expensive.