Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion


The Perflib subkey stores configuration data for the Windows Performance Library, which collects and organizes data for performance tools, such as System Monitor.

In addition to entries, the Perflib subkey contains a Language-code subkey for each spoken language you configure for Windows Server 2003. The Language-code subkey stores performance counter names and their descriptions in the specified language. The Language-code subkey is named for the language code for that language. For example, the counters and descriptions for the English language are stored in a subkey named 009, the language code for English (United States).

Activation Method

To make changes to entries in this subkey effective, restart Windows.


  • If you cannot display particular performance counters, check the Application Log in Event Viewer for events recorded by Perflib. When Perflib finds a disabling error in a performance counter dynamic-link library (DLL), it records an event in the log. Then it sets the value of Disable Performance Counters to 1 to disable the counters.