Many of the commercial Web server software packages (see Chapter 5) that are covered in this book have their own mail server bundled with the software. In these cases, the developers might have used a derivation of either sendmail or smail, or might have used a commercial product (such as Microsoft Exchange used by Microsoft IIS) or have their own unique product that carries out all the routing functions.

Figure 7.4: IIS mail server options screen

In general, if you are using a product that does arrive with its own mail agent, then this will be automatically configured from the information you enter to setup the main Web server application (see Chapter 6 for more details). For example, the configuration software will know the name of the Web server, its domain, the Webmaster's mail address, and the connection to the Internet. For a number of products, such as the Purveyor range of Web software and Luckman's Web Commander, the mail software is part of the package and the Webmaster is not expected to hack the code except to check the settings.

Once you have configured the DNS and the mail server program you will then need to add the user names for the mail routing table for the mail server program. This, again, varies according to the software: some Windows NT software will be able to build the user names from the existing Windows Registry entries, NetWare-based Web servers can often analyse the NetWare NDS...