Optimize Outlook on Exchange

Microsoft Exchange Server 5.5 has several components you can use to improve client, server, and networking performance. You can optimally configure Microsoft Outlook 8.03 to interact with Exchange by using the same techniques you used to optimize previous versions of Outlook and the Exchange client.

Optimizing network communications improves Outlook's startup time. If you misconfigure the client, it might have trouble locating the Exchange server. Two networking configuration areas you need to control are the network binding order and name resolution order. You can also optimize performance if you configure optimal address storage, message storage, and message archival.

Outlook Client Connections
When Outlook needs to communicate with the Exchange server, it establishes a remote procedure call (RPC) connection to the server, based on the RPC binding order you specify in the Registry. Depending on your Exchange and Outlook configuration and how you use the client, Outlook might frequently establish such a connection. An Outlook client connects to an Exchange server when Outlook starts up, connects to your mailbox, opens another person's special folder, and views Microsoft Schedule+ information or public folders.

When Outlook starts up or views special folders, it establishes connections to the Exchange server's private information store. Outlook identifies the Exchange server to connect to from your home server. Your user profile specifies this server. After you connect to your private information store, Outlook establishes a session to your home server and then uses that session for future communication.

Another user might give you access to a special folder. To view the folder, you must establish an RPC connection to the user's home server (which might also be your server). Select File, Open Special Folder, Exchange Server Folder. Specify the user's name and the folder to view.

A special public folder stores the Microsoft Schedule+ free and busy information. By default, the first server in a site contains the free and busy time for users in the site. When you invite users to a calendar-requested meeting, the calendar automatically connects to the public folder to retrieve free and busy information. If your home Exchange server doesn't house the free and busy public folder, Outlook establishes an RPC connection to the server in your site to get the free and busy information.

Multiple servers in a site can house public folders. As with the free and busy information folder, the client establishes an RPC connection to the server that contains the requested public folder. Large Exchange organizations with multiple sites can replicate public folders to all sites for easy access.

A client might have access only to public folders in another site. In this situation, Exchange uses public folder site affinity to inform the client which sites contain public folder servers and what order to use in connecting to them (based on affinity value). If the requested public folder is not on a server in the client's site, the client connects to other Exchange sites, in order of affinity, to look for the folder. A client might have to connect to multiple Exchange servers in the site before it finds the requested folder. Thus, a quick RPC connection between the client and Exchange servers is important.

RPC Binding Order
To connect to the Exchange server from Outlook, you must first find the server. This process involves checking the available network paths and resolving the server name. Outlook uses RPCs to communicate with the Exchange server. The RPC binding order determines the order in which networking protocols and applications protocols search for the server. Networks use multiple protocols and network programming interfaces. Outlook is network independent, so it methodically searches for the server on the network interfaces. The RPC binding order on the network interface is specific to Outlook and Exchange and is not related to the network binding order in Control Panel.

When an Outlook client communicates with an Exchange server, it uses the RPC binding order identified in the Registry to determine the appropriate protocol and interface for connecting to the server. Table 1 lists available transports.

The default binding order for a Windows NT or Windows 95 client is ncalrpc, ncacn_ip_tcp, ncacn_spx, ncacn_np, netbios, ncacn_vns_spp. The Outlook client attempts to use the first transport in the Rpc_Binding_Order Registry line. The client waits for a transport to time out before attempting to use the next transport listed. To improve connection time to a server, edit the binding order so the client uses the first binding in the list to connect to the server. The binding order you use depends on the protocols your server and client support. On TCP/IP protocols, the binding order depends on the name resolution mechanism.