If you have installed Windows 98 on a computer that had any Windows Messaging components on it, they will be left intact. These components, which include Microsoft Exchange, Internet Mail, and Microsoft Fax, will continue to function as they did with your old operating system, and your e-mail icon will remain on the desktop unless you remove it.
The first time you click the Outlook Express icon, Windows detects the presence of any other e-mail programs, and asks if you would like to make Outlook Express your default e-mail client.
The core of the Windows Messaging subsystem is the messaging application programming interface (MAPI), an industry standard that enables applications to interact with many different messaging systems using a single interface. MAPI is a set of API functions and object linking and embedding (OLE) interfaces that allows messaging clients, such as Microsoft Exchange, to interact with various message service providers, such as Microsoft Mail and Microsoft Fax.
The Exchange and Outlook e-mail clients also provide features like scheduling, groupware applications, and custom application development. If you need this additional functionality, you may want to keep one of these e-mail clients on your system, or if you do not currently have them, you can install them.
To download the Microsoft Exchange mail client, go to the Windows Update Web site at http://www.microsoft.com/windows95/info/exupd.htm.