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I have a mail server set up using virtual users and postfix that i can send mail through using my Windows Phone 8 mail client but when i try and send a test email through Outlook 2013 with or without TLS enabled Outlook times out. "Outlook cannot connect to your SMTP server" but i see no connection attempt in my mail.log Also i can send when I am on the same network as my server, just not when I am on an outside network. ANy ideas?

Thanks, Nat

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What SMTP port are you specifying in outlook? Some providers will block outgoing traffic on port 25, in which case you might need to enable the submission port (587) in the postfix file on the server side, and specify 587 as your outgoing port in outlook on the client side.

submission inet n       -       n       -       -       smtpd
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port 25, but i can still send from my phone, just not outlook. SO the port is not being blocked, i am using a self signed SSL cert, could that be it? – Nat45928 Mar 19 '13 at 12:03
If it's this issue it would be the client side that has the problem, and not all clients equally. When you said "I can send when I am on the same network as my server, just not when I am on an outside network." that made me think whatever that other network is is getting g port 25 blocked. – vjones Mar 19 '13 at 15:18
Yeah, i understand, i have no clue what this is and it's driving me nuts. – Nat45928 Mar 19 '13 at 15:19
It could still be this port 25 thing, but it's up to you if you want to try the fix or not. It's an easy change to make. Actually that line I gave you is in already - you just have to un-comment it and do postfix reload. Then change outlook to use port 587. – vjones Mar 19 '13 at 15:26
Well, you were right, worked like a charm. All the votes to you my friend. – Nat45928 Mar 19 '13 at 17:16

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