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My Zimbra mail server, which uses Postfix, is working fine.

I am able to receive mail at 25 from Yahoo, Hotmail etc., but if I block my 25 port for incoming then mail will stop to come into my mail server as my secure SMTP port 465 is already running.

So is there any way to receive mail at another port like on 465 insted of port 25?

Thanking you,

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The general answer is - NO.

The reason is that while you CAN put your server to receive on that port, the other servers i the world will send their email to port 25, and you can not change that.

This is part of the SMTP specficiations, and while you are free to configure your server different - that is of no practical use unless the rest of the world cares about your server, which - they do not. They just try to send to your default port.

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thanx, but earlier i already configure zimbra mail server with postfix where i have block my port 25...and still it will receive mail from yahoo,hotmail etc... but i forget that how had i done that?..may be it will receiving mail at port 465 .... – sadiq Mar 18 '10 at 10:09
No, you won't - at least not from external SMTP servers which will always use the well-known port for SMTP: 25/tcp. – joschi Mar 18 '10 at 10:14
TCP port 465 is reserved by common industry practice for secure SMTP communication using the SSL protocol - as you can see 465 IS a standard. Make sure you have proper SSL certificate installed ;) – TomTom Mar 18 '10 at 10:15
Most/All mail servers default to using the standard port 25 for SMTP email. Some mail servers, who support TLS for sending email through encrypted transport) AND also support sending email through port 465 (another standadard for sending TLS encrypted email). Your experience is showing that the big mail servers (like yahoo, hotmail) will send at port 25 or port 465. If those people are enough for you, then your set up is fine. People connected to mail servers without support for sending to port 465 will not be able to send you email. – samt Aug 16 '11 at 0:31

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