Microsoft supplies its Exchange e-mail client software with Windows 95 (covered in Chapter 6). This is a full-featured messaging system for small networks. It's an excellent choice for peer-to-peer networks, since it provides a single point of collection for the mail messages from the local network, Internet, fax messages and other on-line services. However, as your network grows so the limitations of this basic client software appear.

The main problem is that in its client form supplied it can only support a single post office you cannot exchange messages between two or more post offices. In order to install post offices that can communicate and exchange messages you will have to upgrade the post office from the client software to the server software. You can buy this upgrade either in the form of Microsoft Mail Server or Microsoft Exchange Server platforms. In both cases, the client software remains the same and the server post office software runs on a separate post office computer.

A great advantage of upgrading the client post office software to the full-fledged server version is that the server post office can support gateways. This means you can exchange mail messages with other mail systems. For example, Microsoft Mail Server supports gateways to MHS (a common mail standard), X.400, CompuServe, MCI, fax and pagers.

Figure 7.6: Exchange client supplied with Windows

If you are considering upgrading your Exchange client post office software in order to provide a better service to your users, or if...