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Hello My server is Ubuntu LTS 10.04 Installed and configured postfix with sasl, courier and virtual domains with mysql behind them. everything is working except for sending of email to outside domains.

here is the configuration

here is the verbose smtp log of an unsuccessful send.

I'm testing this from squirrel on the same server, and can't actually test form outlook since my local ISP is blocking outside smtp connections on port 25.

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up vote 1 down vote accepted

It looks like Squirrel did not authenticate to your Postfix server using one of the login mechanisms. It's OK since you were already authenticated to Squirrel, you should just correct your Postfix config a bit. You should set mynetworks to to allow Squirrel to send emails, like this:

mynetworks =

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Ok, this worked for sending from squirrel, How can I test to see if sending from an outside client will work? problem is my isp blocks outgoing to port 25 – cromestant Feb 3 '11 at 11:54
also, why didn't the mynetworks = all work? – cromestant Feb 3 '11 at 11:55
I don't think all is a proper configuration value for mynetworks, it should be if you want to enable any IP to send email through your MTA. Actually, you don't want to enable anyway, because setting it to will effectively turn your MTA to an open relay. That's not a good idea since every spammer will be able to utilize your open relay to send SPAM. It's better to leave mynetworks set to – Alex Feb 3 '11 at 12:06
You can test sending from an outside using a port different from 25 temporary. Ports are configured in /etc/postfix/ The default port is defined in this line: smtp inet n - - - - smtpd You should change the first smtp to some other numerical value, like this:1025 inet n - - - - smtpd (It will use port 1025 then) – Alex Feb 3 '11 at 12:09
ok thank you for your explanation. – cromestant Feb 3 '11 at 12:09

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