How is the Change Password feature implemented in OWA?

The change password feature is not enabled by default in OWA 2000 because it is a feature of IIS, not Exchange 2000 Server. The IISADMPWD virtual directory must be created in IIS under the OWA website and the Change Password button must then be enabled from within the registry.

For more information refer to https://support.microsoft.com/?kbid=297121.