This article will show you how to setup an email server accessible using a POP3, IMAP or web browser client. It will also show you how to include virus scanning and spam tagging in the mail server. If you have an existing Active Directory or LDAP infrastructure, the last section will show you how to integrate it into your email server so you won’t have to maintain two sets of user accounts.
How to install Linux
You can use either Red Hat Enterprise Linux 5 or CentOS 5. RHEL 5 can be purchased from Red Hat and comes with support. CentOS 5 on the other hand can be downloaded here.
How to install SMTP, POP3, IMAP and Webmail service
Postfix will be providing the SMTP service, Dovecot will provide the POP3 and IMAP service, while Apache and SquirrelMail will provide the Webmail service.
How to create mailboxes and do miscellaneous tasks
This section will show you to do tasks like creating mailboxes, aliases, setting quota etc.
How to add antivirus and antispam filtering
We will be using Clam AntiVirus for virus scanning, SpamAssassin for the spam tagging and MailScanner to integrate them into Postfix.
How to integrate Active Directory/LDAP
Integrating Active Directory/LDAP into your mail server will turn your Linux email server into a lean and mean Exchange like machine. And you won’t have to deal with Linux system accounts or edit configuration files for common tasks like creating mailboxes and mailing lists. And finally, you can provide your users with standard address book.
Using Winbind to integrate Active Directory user accounts.
Another way to integrate Active Directory into your mail server. I highly recommend using the virtual user solution above instead of this one.
How to integrate MySQL or support multiple domains
To simplify administering multiple domains, the domains and mail accounts will be stored in MySQL and will be managed using Postfix Admin, a web based interface for handling domains, mailboxes and aliases.
Install the SquirrelMail Postfix Admin Plugin if you want to enable the users to set their own vacation message, forwarding and password.
Visit the forum to ask for help or to give a comment.
REFERENCE
http://www.linuxmail.info/mail-server-setup-centos-5/