The general way to get the system variables is such
Set WshShell = WScript.CreateObject("WScript.Shell")
Set WshSysEnv = WshShell.Environment("SYSTEM")
WScript.Echo WshSysEnv("WINDIR")
Sorry I was late

btw... Outlook forms are EVIL
I believe you could also use
objFSO.Copy "C:\Initial File\Dir\test.txt", "%ADMIN%\"