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I am running MAMP Pro on my machine with all empty Postfix values. Yet, whenever my PHP application calls mail(), mail is being sent out from my machine. In a production environment this would be fine but I am in a development environment. how can i disable outbound mail in postfix? discusses setting the default_transport = error. However, this setting does not appear in /private/etc/postfix/, additionally, I cannot verify that this is infact what I need. I want to be absolutely sure that mail is disabled. I do want to be able to receive mail from my Entourage client but that's it.

Can anyone help? Many thanks!

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up vote 1 down vote accepted

Do it as described in the provided link. If the line is not present in then add a line with default_transport = error:This server sends mail only locally.

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Thank you. Can you please explain what that means? "This server sends mail only locally"? I assume this means that I can send and retrieve mail only from and to myself but I want to be sure. – syn4k Sep 29 '11 at 17:12
@Noor This is only the reply message. You could even write error:Ha ha. I don't like sending mail. Don't try again – mailq Sep 29 '11 at 20:40

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