In Chapter 3, we discuss how Exchange 2000 uses a cache to maintain details of recently accessed directory information. The cache can be configured through registry settings to determine how often it is flushed and how much data is held. The default values are to hold up to 4MB of information for up to 10 minutes.

As an example, to adjust the cache to hold 8MB of information for 30 minutes, changes would be made to the following keys:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeDSAccess\Instance0\CacheTTL 

The cache time setting is held as a REG_DWORD in seconds and would be set to 0x1800 (30 minutes = 180 seconds). The cache size is specified as kilobytes, also in a REG_DWORD. To store 8MB we'd insert the value 8192 in:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeDSAccess\Instance0\MaxMemory 

If desired, it is possible to use registry settings to instruct Exchange 2000 to use a specific GC for proxies and referrals. The settings, which are applied in the system registry of the server rather than for each client, are:

HKLM\System\CurrentControlSet\Services\MSExchangeSA\Parameters\NSPI Target Server 

and,

HKLM\System\CurrentControlSet\Services\MSExchangeSA\Parameters\RFR Target Server 

The first setting is used for proxy clients like Outlook 98, the second is used to refer clients that are GC-aware like Outlook 2000. In both cases, the value is a string giving the name of the GC server. For example "GC-SERVER1." It is also possible to force Outlook 2000 clients to always use the DS proxy process to find a GC by disabling referrals on the Exchange 2000 server. Referrals are disabled on an Exchange 2000 server by placing...