>How can i list all the drives wherther local or networked mapped drives. Do i need to use an API function ?? help,please !!

Depending on what's available to you, you can use calls to the Win32API, or simply use the Scripting.FileSystemObject from WSH and access it's Drives collection, which will provide a tremendous amount of information by traversal of the Drives collection:

oFSO = CREATEOBJ('Scripting.FileSystemObject')
FOR EACH Drive in oFSO.Drives
   ? Drive.DriveLetter,Drive.AvailableSpace,Drive.DriveType
ENDFOR

See the WSH docs in the MSDN, or through th WSH-related sites in my sig block.