CDO & MAPI Programming with Visual Basic:

Chapter 12. CDO for Windows 2000

CDO for Windows 2000 shares its name with CDO 1.21, and that’s unfortunate. It gives the impression that CDO for Windows 2000 is the latest, greatest, updated version of CDO. Unfortunately, that isn’t so. CDO for Windows 2000 and CDO 1.21 are different products altogether. The purpose of CDO 1.21 is to give Automation clients easy access to MAPI. In contrast, CDO for Windows 2000 is oriented toward server-side programs that need to send and receive Internet email and newsgroup postings. Visual Basic developers who wish to access MAPI’s powerful features will continue to use CDO 1.21.

Because CDO for Windows 2000 is not MAPI-based, this book doesn’t go deeply into its features. Rather, this chapter gives an overview of what those features are and provides samples of sending and receiving plain-text email. Posting to and reading from newsgroups are not discussed.

Before going further, you might wish to turn to Appendix A, and read the first two sections to get an overview of how Internet email works. This chapter uses certain terms (such as Simple Mail Transport Protocol [SMTP]) defined in those sections.

Getting Started

All versions of the Windows 2000 operating system include CDO for Windows 2000, so there is no need to obtain and deploy this component separately. However, some features of CDO for Windows 2000 require the use of Microsoft’s SMTP service. This system service is included only in server versions of Windows 2000 and in Internet Information ...