HOWTOForge is a great place to pick up some great guides on setting up your server. Here: This guide describes how to set up a full email solution in Debian Linux (all code is from Debian Etch). I was asked to design a secure, scalable, portable solution for a small company. He goes through every stage, from soup to nuts, of all the issues and steps involved in getting your mail up to the level you want it at.

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