Dim objFSO, objFldr
sPath="F:\Files"
Set objFSO=CreateObject("Scripting.FileSystemObject")
Set objFldr=objFSO.getfolder(sPath)
iSize=objFldr.Size  'size in bytes

WScript.Echo "Folder size for " & sPath & " is " &_
 FormatNumber(iSize/1048576,2) & " MB"