"Thomas P. Carter" <[log in to unmask]> writes:
> I wrestled with this the other day, but on an IMAP link with Outlook
> 2003. The port required for sending is now 465 instead of the normal 25.
>
> I suspect they recently changed this port number and broke the user's
> connection, but I have no hard evidence for this. Making this change
> fixed it. POP clients are now required to use port 465 (and SSL) for
> outgoing mail also, evidently.
IMAP/POP are of no consequence when sending mail.
We have been running on both 465 and 25 since we created mail.msu.edu.
465 runs SMTP protocol over TLS|SSL which does a tls-on-connect. This
is different from having to send the SMTP command STARTTLS via port
25. Different clients do things differently, which is why we support
both mechanisms (and consequently both ports). We have not changed
this configuration since mail.msu.edu's inception. We have noticed
that clients (specifically Outlook) seem to change requirements from
version to version (either doing STARTTLS -> AUTH {25}, or doing
tls-on-connect {465}).
Hopefully this helps.
./muk
--
m. kolb <[log in to unmask]>
