Microsoft® Office Outlook® 2003 works well with a variety of e-mail servers, but you can take advantage of a richer feature set by using Outlook with the latest version of Microsoft Exchange Server. Some Outlook 2003 features require certain Exchange versions (and, in some cases, specific Exchange configurations running on certain versions of Microsoft Windows®), while other features work better with newer versions of Exchange.
Warning If you plan to use Microsoft Exchange Server 5.5 with Outlook 2003, you should install a critical update for Exchange Server before upgrading client computers to Outlook 2003. Choosing to use Outlook 2003 with Exchange Server 5.5 without the update can cause Exchange Server to encounter an error and stop responding. For more information, see the Knowledge Base article XADM: Information Store Intermittently Stops Responding and an Access Violation Occurs in EcDSDNFromSz.
Several features of Outlook 2003 work best with Microsoft Exchange Server 2003 or later, especially for mobile users accessing their mailboxes over slower connections. This is apparent for the new remote procedure call (RPC) over HTTP feature, which enables users to log on to Exchange Server 2003 servers behind the corporate firewall without needing to use a virtual private network connection. Furthermore, the exchange of information between the Outlook client and Exchange Server is more efficient with Exchange Server 2003 because of the new data compression and partial-item update features. Also, on slow connections using the Headers Only mode in Outlook, an expanded plain text header preview now gives users more information to help them decide whether to download the full item or not. Finally, transactions between Outlook and Exchange Server 2003 are now more robust for the following reasons:
- Scenarios that previously caused synchronizations to fail are now managed so the synchronization can continue.
- Updates are checkpointed. This means that if a download of new information is interrupted — for example, by a connection failure — Outlook can resume the update at the point where the failure occurred, instead of starting over from the beginning.
These enhancements work together to help ensure that Outlook users accessing Exchange Server 2003 servers remotely over slower connections have a better user experience.
Outlook 2003 and e-mail protocols and servers
Outlook 2003 can be used with a wide variety of e-mail servers and services. The primary e-mail servers and services supported by Outlook include:
- The Simple Mail Transfer Protocol (SMTP)
- The Post Office Protocol version 3 (POP3)
- The Internet Mail Access Protocol version 4 (IMAP4)
- The Messaging Application Programming Interface (MAPI) for Microsoft Exchange Server
- The MSN/Hotmail DAV/HTTP Protocol
- Other messaging and information sources, including Hewlett-Packard OpenMail, Banyan Intelligent Messaging, or IBM Lotus Domino
Use of Outlook 2003 with Domino R5.x and later requires the Microsoft Office Outlook Connector for IBM Lotus Domino to be released by Microsoft in the first half of 2004.)
Outlook can also be used with a number of other messaging and information sources, including Hewlett-Packard OpenMail and Banyan Intelligent Messaging. Use of these additional service providers is made possible by the way that Outlook uses the MAPI extensibility interface.
If users want to use the Contacts, Tasks, and Calendar features in a stand-alone configuration, they can also use Outlook without an e-mail server.
The following sections list the new features supported only when Outlook 2003 is used with Exchange 2003 or later. It also lists the features that work better when Outlook 2003 is used with Exchange 2003 or later.
Outlook 2003 features supported only with Exchange Server 2003 or later
Using Outlook 2003 with an Exchange Server 2003 or later messaging server has a number of advantages. For example, the following Outlook features work only with Exchange Server 2003 or later:
- Cached Exchange Mode using Download Headers
Cached Exchange Mode automatically downloads only headers when a user's connection mode is perceived by the user's operating system to be slow.
- Cached Exchange Mode using Download Headers and then Full Items
With this option, all item headers are downloaded first, followed by item bodies and other detailed information. Users can choose to see specific items right away (headers as well as item bodies and attachments) by clicking item headers.
- RPC over HTTP connection support
You can configure user accounts to connect to an Exchange server over the Internet. This feature allows users security-enhanced access to their Exchange Server accounts using the Outlook 2003 client when they are traveling or are working outside their organization's firewall.
Outlook can use Kerberos authentication with Exchange 2003. The Kerberos network security protocol uses cryptography to help provide mutual authentication for a network connection between a client and a server (or between two servers).
- Performance tracking support
Outlook 2003 provides information about client processing that Exchange can use to help track down networking or server problems. For more information, see Exchange Server 2003 documentation.
Outlook 2003 enhancements that work better with Exchange Server 2003 or later
Exchange Server 2003 and later versions of Exchange Server provide support for new features in Outlook 2003, but Outlook 2003 also works better with Exchange 2003 or later in several ways — most notably for synchronization processing, user synchronization status reports, and junk e-mail filtering.
Synchronization processing between Outlook and Exchange has been enhanced in a number of ways. For example, data exchanged between the Outlook 2003 client and Exchange 2003 servers is now compressed, and the data buffer size is larger. In addition, the buffers themselves are now packed, so more compressed data is included in each buffer. With these improvements, more data can be transferred with fewer server calls. This is especially beneficial when users are synchronizing across networks that charge by the byte of data that is transmitted. When large information sets are being downloaded — for example, when users update mailboxes after being on vacation — cost can be significantly lowered, and the transaction shortened, with these improvements.
Another improvement that users will notice is better status information about Cached Exchange Mode synchronization with the Exchange 2003 server. With Exchange 2003, the Outlook status bar shows detailed information about synchronization such as:
- How many bytes have yet to be downloaded for the current folder.
- How many items have yet to be downloaded in the current folder.
- Approximately how long it will be until the current folder is synchronized.
- Folder status such as Up to Date and Last updated at <date and time>.
In addition, the Headers Only mode in Outlook 2003 — when used with Exchange 2003 — provides a 256-byte plain text preview that includes part of the message body, rather than showing just the message header information. This message preview can help remote users to make better decisions about whether to download a whole message — which, for example, might include a large attachment.
Finally, using Outlook 2003 with Exchange Server 2003 or later helps to provide a better experience for users in filtering junk e-mail messages. The new Junk E-mail Filter in Outlook 2003 provides some support for Outlook 2003 users with Cached Exchange Mode on versions of Exchange Server earlier than Exchange Server 2003. However, with Exchange Server 2003, the experience is much improved. To learn more about how Outlook junk e-mail filtering is supported with different versions of Exchange Server, see Helping Users Avoid Junk E-mail Messages in Outlook 2003.
When you use Outlook 2003 with Microsoft Exchange Server-based systems, you can use Cached Exchange Mode and other features to enhance the user experience with regards to high latency, loss of network connectivity, and limited network bandwidth. Download the Client Network Traffic with Exchange 2003 whitepaper to learn about these new enhancements.
You can configure Microsoft Exchange Server settings for Outlook profiles as part of your Outlook 2003 deployment. For more information about using the Custom Installation Wizard to customize Outlook profiles, see Customizing Outlook Features and Installation With the Custom Installation Wizard.