By Prince McLean

Published: 09:00 AM EST

One of the most anticipated applications in Office 2008 is the new Entourage. While some users can use alternatives to Word, Excel, and PowerPoint, most of the users of Entourage are required to use it to access an Exchange Server for their mail and calendar. The reason for that has a lot to do with Exchange itself. Here's a look at the new Entourage in comparison to using Apple's built-in Mail, Address Book, and iCal.

This report goes to great lengths to explore the origins, history, and maturity of Microsoft's e-mail applications. For those readers with limited time or who are only interested in what's due in Entourage '08 as part of Office 2008 for Mac, you can skip to page 2 of this report.

The Birth of Entourage: Exchange Server

In 1996, Microsoft released the first version of its new email server as Exchange 4.0, numbered to suggest itself as a replacement for the former, unrelated Microsoft Mail 3.x and to associate it with Windows NT 4.0. Exchange was designed around the ill-fated OSI X.400 email and X.500 directory server standards. However, just as Microsoft was preparing to introduce Exchange, those standards were steamrolled by Internet standards: POP and IMAP email and LDAP directory services, as described in Road to Mac OS X Leopard: Parental Controls and Directory Services.

Caught blindsided by the Internet, Microsoft dramatically changed course in 1996. It licensed the SpyGlass browser and released it as Internet Explorer, and paired the browser with a hastily written "Internet Mail and News," which served as the Windows client for Internet email.

At the same time, Microsoft sold Exchange as a proprietary email system that could optionally also be connected to the Internet via an email gateway. Client machines had to use a specialized mail program to talk to Exchange Server called Exchange Client. Rather than using standard email protocols between the server and client, Exchange Client used a mix of undocumented RPC calls, generally referred to as MAPI, the Messaging Application Programming Interface proprietary to Windows.

That left Microsoft in 1997 with two email programs: Internet Mail and News for standards-based email, and Exchange Client for use with its own server product. Exchange also provided a webmail portal as part of Exchange Server called Exchange Web Access. To obfuscate the confusion, Microsoft renamed all of its client products under the Outlook brand:

• Exchange Web Access became Outlook Web Access (webmail)
• Internet Mail and News became Outlook Express (Internet email)
• Exchange Client and the Schedule+ calendar were replaced with Outlook (MAPI email, calendar, contacts, tasks, notes)

Microsoft bundled the new Outlook with Office 97 (below), and gave it an 8.0 version number to match Word. That same year, Exchange Server 5.5 shipped with rebranded Outlook client software for Mac, DOS, and 16-bit versions of Windows.



Microsoft and the Internet

Outlook could only be used with Exchange Server, while Outlook Express could only be used with Internet mail. The next year, Microsoft changed Outlook on Windows so that the user could choose between installing the application as a MAPI-only Exchange client, or alternatively install POP/IMAP support instead. That option basically installed Outlook Express underneath, which worked entirely differently, but appeared to be "Outlook."

The groups inside Microsoft working on Mac versions of Internet Explorer and Outlook Express were combined in early 1997 to form the Macintosh Business Unit. That group was charged with developing competitive versions of Internet applications for the Mac with the goal of destroying Netscape's cross platform advantage as detailed in Microsoft's Plot to Kill QuickTime. The Mac version of Office was also growing very old and sales were beginning to sag, so Microsoft additionally assigned the MacBU to release a new version of Mac Office.

That year Steve Jobs also regained control of Apple and began working to prioritize worthwhile projects and kill hopeless ones. Without strong leadership, Apple had also allowed Microsoft to coast on a variety of patent infringements related to operating system technologies and QuickTime. Apple's San Francisco Canyon case against Microsoft, described in Mac Office, $150 Million, and the Story Nobody Covered, was also still waiting to be resolved.

The MacBU

To resolve all those issues, Apple and Microsoft partnered in an agreement that included Microsoft making a good faith gesture of investing in Apple and publicly committing to deliver five years of updates for Office. That resulted in Mac Office 98, which shipped alongside the free Mac Outlook Express email client and Internet Explorer browser, which Apple agreed to bundle and present in front of Netscape's existing browser.

It also played into Apple's dismantling of its Claris subsidiary in 1998; it sold the Claris Organizer calendar to Palm for recycling as the Mac Palm Desktop software and dropped the highly regarded Emailer (below) entirely, as described in Office Wars 1 - Claris and the Origins of Apple iWork. Apple also closed down its own OpenDoc and CyberDog efforts related to building parts for web and email services. That resulted in a deluge of Apple software refugees ending up at Microsoft, including Claris Emailer developers Jud Spencer and Dan Crevier.



In 1999, Microsoft put new hire Omar Shahine and his roommate Jimmy Grewal in charge of the Mac Outlook Express and Internet Explorer projects, respectively. Shahine described their experience at Microsoft in Entourage: A journey to becoming an Office application, writing, "Two 22 year old punks who never shipped anything in their lives shipping what became the most popular browser and mail client on the Macintosh. I remember going over to Apple for meetings some times and they would be like, are you kidding? Where are your parents?"

Outlook Express subsequently inherited many of the features of the former Claris Emailer and was developed entirely separate from the Windows version of the same product name. The product also morphed into an app more tightly integrated with Office, in order to serve as a complement to Outlook in the Windows Office package. There was already a Mac version of Outlook, but it was completely unrelated to Outlook Express and had been developed by the Exchange team rather than the MacBU. It also lacked Internet email support.

Entourage vs Outlook

In Office 2001, Microsoft shipped the new Entourage as a Mac-centric email program and a component of Office. While it could talk to Exchange Server, it had to use standard IMAP just like any other email application rather than using the proprietary MAPI. In order to support corporate Mac users, the Exchange group also shipped Outlook for Mac 2001 (below). Microsoft eventually decided that it made no sense to continue development two entirely different products to provide Mac email services, so it focused on the more Mac-like and more modern Entourage, and dropped support for Mac Outlook as Office applications moved to Carbon in order to run on Mac OS X.



Entourage was modified to support WebDAV to enable it to communicate with Exchange Server's web interface. Starting in Exchange 2000, this also became the mechanism Microsoft used for connecting mobile devices to Exchange. Essentially, both Entourage and Palm/Windows Mobile devices act like specialized web clients. This allowed Microsoft to kill the old Outlook for Mac rather than having to retrofit it to work on Carbon.

On the Windows side, Microsoft continued to entrench into MAPI, but mixed in IMAP support so that Outlook could access both standard email and Exchange Server accounts. Outlook Express is now called Windows Mail on Windows Vista.

In Office 2004, Entourage delivered fair support for Exchange Server, but it lacks a variety of features supported in Outlook on Windows. Its performance with Exchange is poor, it lacks calendaring and email features, and it does not support the .pst email database archives of Outlook. While Outlook Express on the Mac used a more standard MBOX style mail storage based on its Outlook Express and Claris Emailer heritage, Entourage stores local email in a database somewhat similar to, but incompatible with, Windows Outlook .ost and .pst files.

On page 2 of 3: Entourage 2008; Entourage 2008 Email; Entourage 2008 Address Book; and Entourage 2008 Calendar.