Introduction to Client Connectivity

As robust and powerful as Exchange Server 2003 is, it is of little use to your users if they cannot access their email, calendars, and other items in an efficient manner. Fortunately, Exchange allows a number of methods to connect users with the information they require. The primary means of connecting users to Exchange is by using Outlook or Outlook Web Access (OWA). Windows users without Outlook installed can use Outlook Express (or many other POP3 or IMAP4 clients) for varying degrees of access to Exchange Server's messaging capabilities. POP3 clients are limited to only basic Inbox access, whereas IMAP4 clients can access multiple mail folders, calendaring information, and public folders. Some of the more advanced features Exchange Server 2003 offers, such as cached mode operation and forms, are only available when using Outlook 2003 as the messaging client.

Outlook 2003 is the preferred client of choice for making connections to Exchange Server 2003 computers. Consider some of the benefits of using Outlook 2003:

• Outlook 2003 provides a means to efficiently block junk email and block unwanted attachments.

• Outlook 2003 is Tablet PC ready and allows for ink markup directly into Outlook.

• Outlook 2003 dynamically changes display preferences depending on the network connectivity status.

• Outlook 2003 features a new Cache mode that allows users to continue to work normally, even when unexpectedly disconnected from the Exchange server.

Outlook 2003 provides a complete messaging solution by providing users with the following tools: messaging, scheduling, journaling, contact management, tasks, and notes. Each of these parts works seamlessly together to form a very powerful and intuitive messaging client solution.

For those remote or non-Windows users you must support, Outlook Web Access (OWA) provides a wonderful means to access the Exchange organization using a Web browser. OWA in Exchange Server 2003 looks, acts, and feels almost identical to Outlook 2003, providing a higher level of user functionality than any version of OWA before it. OWA can be used in any standard Web browser and has two different versions available depending on the browser in use by the remote user.

Rich Experience OWA is available to users using Internet Explorer 5.0 or higher and provides expanded features, such as secure messaging, rules creation and usage, spell checking, and reminders. Basic OWA is available to users using any Web browser and provides basic access to OWA, allowing for the viewing and creation of email messages.

OWA works by making standard Hypertext Transfer Protocol (HTTP) connections to an Outlook server (or a front-end Outlook server) over port 80. The connection can be protected with Secure Sockets Layer (SSL) by installing a server certificate and making the required configuration on the HTTP virtual server.

OWA, in either Rich Experience or the Basic form, does have several important limitations of which you should be aware:

• Address list browsing is not supported, but address list searching is.

• Searching for messages using the full-text index is not possible.

• Access to personal address books on other workstations is not possible.

• Office integration with Outlook is not supported.

• Outlook forms are not available.

• Access to PST files is not possible.