Ask any employee at any modern company with more than 50 employees what their most critical computer application is. Most of them will tell you email without needing a second thought. While the World Wide Web helped fuel commercial interest in the Internet, email is the single top reason why companies are willing to spend the money for Internet connections. Email is an essential part of the workplace for both internal and external communications. On those days when I work from home, it is not uncommon to have no contact with my coworkers except through email.

As email changed from a luxury into a necessity, vendors began to add more features aimed at the corporate audience, such as calendars and shared message folders. Groupware was born. The first groupware applications were limited and crude. They did not scale well and took constant maintenance to stay operating. They had proprietary mailbox access protocols, cryptic command-line and text file configuration interfaces, and usually stored user mailboxes in a hierarchy of files and folders. Yet they worked well enough to become indispensable.

When Microsoft first introduced Exchange 4.0 in March 1996, it was a major step up from MS Mail, its previous messaging solution. At this time, the messaging landscape featured dozens of separate message transfer protocols and formats. It was not uncommon for a single enterprise to have multiple, incompatible mail systems, some managed on a department-by-department basis. There were two standards for inter-organization message transfer and format that looked like they had a chance to become the acknowledged standard. The first was the X.400 protocol, designed to work in tandem with the X.500 directory service over the X.25 network transport. The second was the Simple Mail Transfer Protocol (SMTP), which had been developed to run over the TCP/IP network transport that formed the backbone of the Internet. X.400 was at that time the favorite to become the new standard. It was favored by government agencies, big businesses, and other large organizations because it was a well-designed protocol that tightly meshed with the X.500 directory service. These large enterprises liked the impressive amount of detail and structure offered by X.500. In comparison, SMTP was a loosely defined protocol with no associated directory service. However, the Requests for Comment (RFCs) that defined SMTP were freely available and were much easier to implement than the combination of X.500 and X.400, so there were dozens of SMTP-compatible mail transport applications and gateways.

Microsoft designed Exchange 4.0 by basing it on the X.400 and X.500 protocols. Because the Windows operating system did not include a native directory service, Exchange included its own that worked in tandem with the underlying user account database built into Windows NT. Microsoft built on the simple mail API included in MS Mail (Simple MAPI), extended it, and included it as the default mailbox protocol. Instead of a collection of files and folders, Exchange used the Jet database engine (a variant of the database technology used in Access) as the message store. Finally, Exchange included a variety of connectors to allow it to interoperate with other messaging systems. In order to sell, Exchange had to connect with just about anything. Although Exchange 4.0 missed its original ship date by 39 weeks, it was the first major enterprise server application success story for Microsoft. It had its flaws and exposed flaws in the Windows NT domain architecture, but it worked well enough to generate interest and sales, even in a market dominated by Lotus Notes.

In October 1996—just seven months after the release of 4.0—Microsoft released Exchange 5.0. This release introduced Outlook Web Access, (then known as Exchange Web Connector) included the first usable SMTP connector, fixed a lot of bugs, and incorporated much of the experience Microsoft had gained in helping customers move large MS Mail deployments to Exchange. Microsoft sold its millionth Exchange seat in mid-1997. It also released the first version of the Outlook client, which integrated messaging, scheduling, and basic personal information management features. Exchange 5.5 followed in November 1997 and marked the shift in the mail protocol wars (which had been heavily affected by the commercial success of the Internet) by including a much more capable SMTP connector and support for POP3, IMAP, and NNTP clients. It was the first version of Exchange to attempt support for clustering and fixed many problems with the Jet database implementation, including size limits and robustness issues.

It was during the 5.0/5.5 time frame that I had my first encounter with Exchange. I was a systems administrator with both Windows and UNIX experience and I was familiar with several SMTP offerings. My opinion at that time was that Exchange was bloated, confusing, and ill-designed. If I had ever taken a good look at the competing groupware solutions, I probably would have changed my mind.

Fast-forward to 1999. Microsoft released Windows 2000 Server and Active Directory. Microsoft managed an amazing feat for a company of its size and diversity: it leveraged the institutional experience the Exchange product group had gained with the Exchange Directory Service and used it to make an impressive “1.0” release of Active Directory. New service packs for Exchange 5.5 ensured that it would continue to run on the new version of Windows and take advantage of the increased speed, stability, and performance of Windows 2000, allowing customers to shift to the new operating system without having to migrate to Active Directory. In 2000, Microsoft released Exchange 2000, which had been redesigned from the ground up.

I still fondly remember the first time I installed Exchange 2000 at a customer site. The hardest part of the migration was getting Windows NT 4.0 installed on the new server hardware that would be the Windows 2000 Active Directory domain controller and promoting it to be the primary domain controller (PDC) of the domain. Actually upgrading to Windows 2000 and installing Active Directory was anti-climactic. Exchange 2000 installed like a dream and since it natively spoke SMTP, we had it handling all inbound mail within minutes.

When Paul asked me and Missy to co-write this book with him, I did not have to stop to think about my answer. The best way to learn something is to teach someone else how to do it, and the Cookbook format provides a unique opportunity for learning and teaching new ways to do familiar tasks. It is also a lot of work to research and write. Most Exchange administrators do not have the luxury of time to do this research and could benefit from a thorough set of task-oriented recipes for common and not-so-common tasks. This is the book I could have used when I first started learning Exchange; I hope that you find it useful as well.

—Devin L. Ganger, 3Sharp LLC

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