On Monday 15 Dec 2008, Dinesh Shah (દિનેશ શાહ/दिनेश शाह) wrote:
On Mon, Dec 15, 2008 at 3:42 PM, Raj Mathur raju@linux-delhi.org
wrote:
Nowadays, all SMTP submission is done over SSL port which is generally 993. You need Port 25 only if you want to run your own mail server or your mail provider does not give secure submission.
Please check if the other SMTP submission port(s) are open.
True but still small time ISPs and some web hosting companies do not have the port 587 you refer to. Outgoing email from MUA still has to go over 25. (see below).
Won't help, since you still need to make an SMTP connection, and then negotiate it (using STARTTLS) into a TLS connection. I don't believe there's any way to start a TLS connection directly, though I wuld be happy to be proven wrong.
This is my Out Going SMTP server settings in ThunderBird.
Server Name: smtp.gmail.com Port: 587 user name: <my mail ID> Secure Connection: TLS
As you can see there is no Port 25 anywhere.
As you can see my colleague still needs 25 to be open to send outbound messages.
$ telnet mail.aaaaaa.zzz 587 Trying 97.65.128.80... telnet: connect to address 97.65.128.80: Connection refused
$ telnet mail.aaaaaa.zzz 25 Trying 97.65.128.80... Connected to mail.aaaaaa.zzz. Escape character is '^]'. 220-beta.routhost.com ESMTP Exim 4.69 #1 Mon, 15 Dec 2008 06:56:16 -0500 220-We do not authorize the use of this system to transport unsolicited, 220 and/or bulk e-mail. EHLO 250-beta.routhost.com Hello static-mum-xxxxxxx [a.b.c.d] 250-SIZE 52428800 250-PIPELINING 250-AUTH PLAIN LOGIN 250-STARTTLS 250 HELP