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I have followed the steps that you have said to do, but with no luck. I don’t really want to use MailInABox unless it is a last resort and I really cannot figure out why Postfix isn’t working. Any other ideas?
Do these files exist?
smtpd_tls_cert_file=/etc/ssl/certs/mailcert.pem
smtpd_tls_key_file=/etc/ssl/private/mail.key
If so, who owns the files + directory, and what are the current permissions on each?
If owned by a user other than root, we need to change that, and we can do so by running:
chown -R root:root /etc/ssl
… which will handle recursively setting ownership to root for both files and directories.
We then need to ensure proper permissions are setup. Ideally, this would be chmod 600 for files and chmod 700 for directories, though you could go as low as chmod 400 on files and chmod 500 on directories.
chmod 600 /etc/ssl/certs/mailcert.pem \
&& chmod /etc/ssl/private/mail.key
and
chmod 700 /etc/ssl/certs \
&& chmod 700 /etc/ssl/private/
then restart postfix
service postfix restart
Other Options
If you’d like something a little easier to setup and work with, I would recommend MailInABox. It’ll handle a huge chunk of what’s needed for you with relative ease.