The Basics About Mail Servers

Hello all.

I'm looking to provide webmail to users to a website that I'm currently developing, and allowing them to create their own email addresses via my site. (Something like hotmail - but smaller, and to a specific audience.) From what I've read so far about doing this, I'm going to need a mail server as well as a mail client. I have found several tutorials on creating a (web)mail client, but very little about mail servers, at least in general terms. I've come across all kinds of (open-source) mail servers - qmail, sendmail, postfix, etc., but haven't a clue where to start understanding them or which one to pick as I can't find just some very basics about what I should know when considering this. Can someone point me in the direction of some information about mail servers (and how to choose the one appropriate to your needs), or clue me in on what I should know? How hard is setting up your own mail server? What are potential security holes? What are potential errors? What's the difference between a Linux mail server and a Windows mail server if this will be hosted by a service on the net (my O/S is windows)? How difficult is the configuration? What are the various components of mail servers? (They seem like they should be rather simple to me - receive email from others, store email, send email to others. Why does this have to be so *@#$ difficult?) What are some other questions I should be thinking of?

The only programming language I know is PHP, and I'm rather new to that. Wouldn't consider myself a novice, but I'm by no means an expert.

Thanks a lot to anyone who will help me out with this.

Oh, also, I'm developing this site locally, so any hints about this would be useful.

Rather than build from scratch get an opensource one and set the ball rolling from there. You have raised very many points:- try doing a search on some of those.

most standard linux installs will come with sendmail or qmail I believe the web interface for that would be squirrel mail. I have not setup any linux mail servers but everything I have setup in linux is very easy to find like redhat or just google for it.

I have setup hundreds of groupwise and exchange mail servers though the basics are easy to understand once you start reading and installing. have fun.