>Thank you very much for your prompt reply. I have tried "Windows Management Instrumentation," it works fine on W2K and XP, but fails on W98, do you have any idea? Should I copy some objects/files to W98 to make it work?

Joey,
WMI is part of the OS in Windows 2000/XP/ME. For Windows 95/98 and Nt4, you have to install it. Check out http://www.microsoft.com/downloads/details.aspx?FamilyId=98A4C5BA-337B-4E92-8C18-A63847760EA5&displaylang=en for version 1.5.

HTH.