8 Replies Latest reply: Apr 28, 2014 6:42 AM by SlipstreamQueen
David Wolfe Level 1 Level 1 (0 points)

Have a MAC PRO and MacBook Pro on the same network both running OS 10.8.2 with two identical email accounts having identical settings.  MAC PRO email accounts work as expected; able to send and receive emails.    However on the MacBook PRO, unable to send emails from either account, only receive emails. I have the same email problem when using the MacBook PRO on different networks, like a Hotel.


Consistently get an error message stating “the sender address xxx@comcast.net was rejected by the server smtp.comcast.net.”


Tried deleting the accounts, restarting and entering new accounts; reinstalled OS 10.8.2; but no difference in the problem.

Worked with several layers of Comcast support, trying all sorts of Port and SSL settings, and confirmed my password works on Comcast webmail, but cannot determine why I cannot send email from one Apple computer when the other Apple computer works as expected. All they could do is blame Apple.


What is different about the MAC PRO (early 1998) and the MAC PRO (15-inch Late 2011}?

iCal, OS X Mountain Lion
  • Stokestack Level 1 Level 1 (0 points)

    Bizarre that one computer would work and the other wouldn't.  You're sure that both are logged into your router (and one of them isn't on the neighbor's Wi-Fi or something)?


    I'm having this problem with Comcast, and their "support" is so ignorant that they think it's because my reply-to E-mail address isn't a Comcast one.  They seriously don't understand that outgoing and incoming E-mail is handled by different servers.  They even thought that I could authenticate to the Comcast outgoing server with the user ID and password for my E-mail account at my domain host (which has nothing to do with Comcast).




    Unfotunately those Apple docs posted above don't address this problem.

  • danathetech Level 1 Level 1 (0 points)

    I'm having similar issues with a client's computer network of imacs and macbooks. Same network, but the imac consistantly states that the smtp server for Comcast is offline in the mail app at least. On that same computer, Thunderbird works flawlessly. The Mail app works fine on the other macbooks. I'm at a loss almost having tried alot of settings. You would think that if the several other mac products work with a certain set of settings that the one iMac would work too....I'm starting to think that maybe its the Mail app itself in this case.

  • David Wolfe Level 1 Level 1 (0 points)

    I am having the same Comcast mail problem all over gain with my MAC PRO and MAC BOOK PRO getting the same SMTP errors after I recently returned from vacation where I was using the MAC BOOK PRO at the Hotels, but using COMCAST web mail>  I do not know where to turn.

  • Stokestack Level 1 Level 1 (0 points)

    What was the SMTP error?


    Comcast has messed up their outgoing server somehow.  I got a message about "The sender address something@somewhere.com" was rejected by the server smtp.comcast.net." This of course is absurd, since YOUR E-mail address has nothing to do with sending mail.


    If that's the problem, you're going to have to call Comcast and repeatedly escalate the case until you can find someone with even a basic understanding of how E-mail works.  I had to get a "supervisor" involved, and this person was still so ignorant that she had to call me back the next day after "researching" the problem and still proposing asinine attempts to resolve it.  And it never did get fixed, by the time I left the location at which I needed to use Comcast.


    You need to insist that your reply-to address is irrelevant for sending E-mail.  If you're connected directly to Comcast's network (which you are when you're connected through your cable modem), you should be able to send through their SMTP server.  Period.  That's how Time-Warner and Verizon work, for example.  The first thing you're going to hear is "Well, you're not using your Comcast E-mail account."  IRRELEVANT.  And why would anyone use the obscure Comcast-assigned E-mail address in 2013?


    Good luck.

  • ~Bee Level 7 Level 7 (31,280 points)



    I have Comcast, and thank goodness, I'm not having your problems currently.  I have had problems in the past with email accounts, and like you, I have two Macs.  So I took the MP downstairs next to the iMac, and just went through every single setting in Mail Preferences > Accounts.  It was one typo.  But it could have been one bad proxy setting, or anything else.


    I would recommend you do that. 

    Best wishes for a solution.

  • woodmeister50 Level 5 Level 5 (4,465 points)

    Had this issue once and found this to be the solution:

    1.  Open Mail and then open Preferences.

    2.  Select the Comcast account.

    3.  In the Account Information pane select the Outgoing

          Mail Server dropdown and choose Edit SMTP Server list.

    4.  Select the account and then select Advanced tab.

    5.  Insure that authetication is Password and the correct user name

          is entered and that you have entered the correct password if

          it is there at all.


    It appears that during account creation in Mail, that the password is not

    always added to the outgoing SMTP box or sometimes gets removed

    with upgrades.

  • SlipstreamQueen Level 1 Level 1 (0 points)

    Woodmeister50's post (almost a year old) told me what I need to know. Periodically the Comcast outgoing mail server becomes unavailable (i.e., goes offline and Connection Doctor shows an error). To get it back, I have to go in and re-enter my Comcast password. (Running Apple Mail on OS X 10.8.5)


    Apparently, this is a lot easier than explaining the problem to Comcast (let alone expecting them to fix it).