Why do so few mail providers support Port 587?

Michael G michaelg at amerion.net
Tue Mar 1 16:28:19 UTC 2005

On Tue, 1 Mar 2005 Valdis.Kletnieks at vt.edu wrote:

> On Tue, 01 Mar 2005 09:18:19 EST, Nils Ketelsen said:
> > 2. Port 587 Mailservers only make sense, when other Providers block
> > port 25. My point is: If my ISP blocks any outgoing port, he is no longer
> > an ISP I will buy service from.
> That's not when you need a port 587 server...
> >                                  Therefore I do not need a 587-Mailserver,
> > as I do not use any ISP with Port 25-Blocking for connecting my sites or
> > users.
> Port 587 is for when you take your laptop along to visit your grandparents,
> and they have cablemodem from an ISP that blocks port 25.  Now which do you do:
> 1) Whine at your grandparents about their choice of ISP?
> 2) Not send the mail you needed to send?
> 3) Make a long-distance (possibly international-rates) call to your ISP's dialup pool?
> 4) Send it back to your own ISP's 587 server and be happy?

E) Log into the webmail service my ISP provides.

Opening another port can too easily turn into a whack-a-mole game between 
you, the spammers and ISPs.

There are myriad ways to allow roaming/emergency E-mail activities.  Let's 
not get pigeon-holed here.

Finally, after a week or so of reading this thread, I'm inclined to 
believe it's officially a holy war.  Nobody's changing anybody's minds 
here it seems.  It's two stationary camps arguing.   Can it stop now?


> (Hint - there's probably a good-sized niche market in offering business-class
> mailhosting for people stuck behind port-25 blocks - they submit via 587/STARTTLS
> and retrieve via POP/IMAP over SSL).

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