Comcast: Yet Another Smart Move

I got an email at work today.  The boss at an external unit was having trouble accessing her email from home.  Someone called Comcast at some point, which provided some interesting information: Comcast is blocking port 25.  They claim they’re doing this to stop spam.

Well, spam hasn’t stopped.  Parenthetically, any complaint or inquiry about spam sent to Comcast doesn’t receive a reply.

The issue here is that people who have Comcast internet and use POP3 to get their email are going to find they can get their email but they can’t reply to it.  Helpdesks will pull their own hair out if they don’t know this.  All of the sudden they’ll be getting tons of calls about people not being able to send replies to their email.

If this change applies to all of Comcast, there are going to be a lot of unhappy people.  FIOS adoption will go through the roof, courtesy of Comcast.  That’s an amusing bit of irony.

I had heard about Comcast blocking ports because they didn’t want consumers running their own mail (or other) servers.  You have to upgrade to a commercial account to do this (big surprise there, eh?).

THE SOLUTION

If you’re experiencing this difficulty, you need to use Comcast’s smtp server, regardless of whose POP3 mail you’re receiving.

So you will be able to download POP3 email with the normal settings.  You just have to change the SMTP settings to use Comcast’s SMTP servers.  It will look someting like this: smtp.comcast.net, plus the specific port that Comcast uses.  If you try to use port 25, which is the standard SMTP port, mail sending will fail.

The other possibility is to try port 587, which is an alternate SMTP port.  There is no guarantee that your POP3 email will accept SMTP on that port. If a sufficient amount of a company’s workers need to access email at home, they might have to add port 587 to their email servers (in addition to port 25).

Funny, this is doing nothing to stop spam.  It’s only causing confusion for Comcast customers.

I am a Comcast internet customer but have not experienced this, largely because I have had no reason to try it.  Comcast notified me two years ago to start using a different SMTP port and I did, with no difficulty.  I had to dig to figure out what they were saying, as they distributed an executable file that would do it for you automatically.  Unfortunately these don’t run on linux (you guys are way ahead of the curve at Comcast).  Or Mac, for that matter.