Many of you hand over personal data to huge corporations. That is particularly true for messaging services like mail, chat or calendars. Those services are on first sight free of charge, you purchase those services with your personal data and that’s a great deal for the majority of users. So using third party messaging services is basically a decision of whom to trust.
For that you may in exchange expect an easy to use and always available service which is in accordance to state of technology, especially with regard to security.
In my opinion you shouldn’t expect that (anymore). Just remember the most recent LinkedIn or Last.fm password leaks or – that truly is another field – just monitor new approaches to lawful interception of your personal data, e.g. upcoming legislation in Great Britain.
Those could be reasons for a decision to regain control over your personal data, starting with a virtual mail server which resides completely within an encrypted FreeBSD Jail. The following guides and HowTo’s have proven very helpful but everyone has different needs. And since you need to administer your server in the future yourself, you should be aware of what you’re doing, instead of setting up a service blindly following an HowTo. So this basically is a small collection of ideas:
Before investigating any particular error with postfix and dovecot, make sure that your jailed postfix instance really listens on the desired port at your host (e.g. like this) and be sure to have your DNS settings straight. Check and overview your MX records with mxtoolbox which has proven to be very helpful.