How to Remove the Initial Memory Percentage Registry Value
The Initial Memory Percentage registry setting was introduced as mechanism for fine tuning the initial amount of memory allocated to the Exchange information store to 10 percent of the total physical memory in the Exchange server. By starting out with this initial allocation and then growing from there, virtual memory fragmentation does not occur as frequently. This registry value should not be set arbitrarily, and should only be used on the advice and direction of Microsoft Product Support Services (PSS).
Exchange Server 2003 includes support for special startup switches in Windows 2000 Advanced Server and Windows Server® 2003 that help reduce virtual memory fragmentation, and additional changes were made to help prevent virtual memory fragmentation in Exchange Server clusters. Therefore, the Initial Memory Percentage registry value is no longer needed on Exchange Server 2003.
The Initial Memory Percentage registry value works only on computers that are running Exchange 2000 Server. Exchange Server 2003 will ignore this value if present, and the value will have no effect. Therefore, you should remove this registry entry before upgrading this Exchange Server from Exchange 2000 Server to Exchange Server 2003.
Before You Begin
Before you perform the procedure in this topic, be aware that the procedure contains information about editing the registry.
Warning
Incorrectly editing the registry can cause serious problems that may require you to reinstall your operating system. Problems resulting from editing the registry incorrectly may not be able to be resolved. Before editing the registry, back up any valuable data.
Procedure
To remove the Initial Memory Percentage registry setting
Start Registry Editor.
Navigate to HKLM\System\CurrentControlSet\Services\MSExchangeIS\ParametersSystem
In the right pane, delete the Initial Memory Percentage registry value.
Close Registry Editor and restart the Microsoft Exchange Information Store service for the change to take effect.
For More Information
For information about a known issue when you use this registry value, see Microsoft Knowledge Base article 810883, ""Initial Memory Percentage" Registry Value Has No Effect" (https://go.microsoft.com/fwlink/?LinkId=3052&kbid=810883).
For information about how to edit the registry, see Microsoft Knowledge Base article 256986, "Description of the Microsoft Windows Registry" (https://go.microsoft.com/fwlink/?linkid=3052&kbid=256986).