This section of the reference describes extension commands that are primarily used during user-mode debugging.
The debugger will automatically load the proper version of these extension commands. Unless you have manually loaded a different version, you do not have to keep track of the DLL versions being used. See Using Debugger Extension Commands for a description of the default module search order. See Loading Debugger Extension DLLs for an explanation of how to load extension modules.
Each extension command reference page lists the DLLs that expose that command. Use the following rules to determine the proper directory from which to load this extension DLL:
If your target application is running on the free build of Windows 2000, use w2kfre\Ntsdexts.dll.
If your target application is running on the checked build of Windows 2000, use w2kchk\Ntsdexts.dll.
If your target application is running on Windows XP or a later version of Windows, use winxp\Ntsdexts.dll.
In addition, user-mode extensions that are not specific to any single operating system can be found in winext\Uext.dll.