When I was developing on a PC, I used a program called PostCast (http://www.postcastserver.com/) to act as my local SMTP server and catch any messages that my web applications generated. It then had a GUI where I could view the messages as if I were on the receiving end. The server could also be configured to never actually send the messages but hold them indefinitely until I manually removed them. This worked out great especially when I was testing against real customer data.

I've since moved on to a Mac and I've yet to find a good way of doing the same thing. For now, I've just been manually changing all of the email addresses to my own and viewing them in Gmail, but I would prefer to be able to mimic the functionality I had in PostCast. Is there a similar way of doing this on Snow Leopard? (I've currently got PHP configured to use the built-in postfix mail server. FWIW, I don't use any desktop mail applications [e.g. Mail.app] and shouldn't really ever need to actually send email directly from my machine.)

  • Using postfix, there are two options that immediately spring to mind: rewrite the To: header to a mail address of your choosing (serverfault.com/questions/77668/postfix-rcpt-to-switch) or deliver all mail locally (serverfault.com/questions/94640/…). If you'd prefer to use another OS X app over postfix, please specify in your question. Commented Nov 20, 2010 at 8:21
  • I don't care if the backend uses postfix or not, though that would be easiest since MAMP is already configured to use it. I would rather not have the mail delivered anywhere at all honestly. I just want it helld in a folder until I remove it, but I also need a way to view the message as an end user would (i.e. via an email client interface) Commented Nov 22, 2010 at 1:11
  • BTW: the second post you linked to does seem to be barking up the same tree, but I can't find any info on how to run smtp-sink, or even where it's installed. A simple which smtp-sink on OSX 10.6 returns nothing. Commented Nov 22, 2010 at 1:27
  • 1
    I know this is a super, super old post, but I've found where smtp-sink lives (on OSX 10.9 at least): /usr/libexec/postfix/smtp-sink
    – rossipedia
    Commented Oct 27, 2013 at 16:54

2 Answers 2


I know this is a late response, but there is a native Mac app to do this now: MockSMTP. Works great and does exactly what you want.

  • Sorry for the delayed response. I've been meaning to try this program out and haven't yet gotten around to it. If you tried it, how has it worked for you in the last month? Commented May 24, 2011 at 13:03
  • I've finally had an opportunity to try this with a few applications, 1 PHP and 1 Rails. It definitely does exactly what I needed it to. Thanks for the tip! Commented Jun 16, 2011 at 12:19

I've done this using DoveCot on my Mac Mini Server (running OS X 10.6 Server). I can configure it to cache sent messages to a folder, and since the Mini Server is the web server, messages are sent from it (the web server uses DoveCot for outgoing mail). I hope this helps.

  • 1
    Unless this "DoveCot" is something different from the Dovecot I know and have been using for years, it doesn't handle outgoing mail at all; it's strictly a POP/IMAP service. You need to configure your MTA appropriately to capture the outgoing emails. Commented Nov 20, 2010 at 6:09
  • Excuse me, Dovecot/Postfix
    – Everett
    Commented Nov 20, 2010 at 6:21
  • Everett: can you provide any instructions on what you did to accomplish this? Commented Nov 22, 2010 at 1:28
  • Using the ServerAdmin utility, select the server on the left side, then Mail. Once that service is open, click on settings at the top. The 5th box under Enable SMTP email is "Copy all mail to:" If you want you could also "Copy undeliverable mail to:" and have it intentionally sent to an email address that doesn't exist.
    – Everett
    Commented Nov 22, 2010 at 4:00
  • Ah, I'm not on a server, just a MBP, so I don't think those options are available to me. Commented Nov 22, 2010 at 4:54

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .