comcast blocking smtp25

David Hummel dhml at comcast.net
Fri Jul 15 10:59:39 EDT 2005


On Fri, Jul 15, 2005 at 06:38:27AM -0400, Jerry Feldman wrote:
> 
> On Thu, 14 Jul 2005 23:48:09 -0400
> David Hummel <dhml at comcast.net> wrote:
> 
> > Right, starting with the whole AOL fiasco a while back.  Nonetheless,
> > Comcast does selectively block SMTP out, which is even worse.  I don't
> > see any reason not to use the smart host, which solves both problems.
>
> It's not that comcast blocks port 25, it does not,

Yes, they do, _at least in my area_.  Confirmed by my own port scanning
and at least two different upper tier Comcast technicians.

Other ports being blocked in my area:

  135 up/down
  139 up/down
  445 up/down
  80  up

YMMV.  Apparently the general policy is to not block SMTP up.

> many recipients, such as AOL will reject Comcast dynaic addresses
> causing you to use another SMTP host.

As Matt already mentioned.  And the solution is to use smtp.comcast.net
as I already mentioned.  But (as Jeff points out) Comcast still has lame
restrictions on outbound mail.

-David



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