Okay, trying to modify this script to disjoin a workstation from the domain. Thought I could just change the bit flag to 4, but I am getting error 2691, "The machine is already joined to the domain."

 Code:
$ou = 'OU=MySubOu,OU=MyOU,DC=MyDomain,DC=com'
$user = MyUser
$password = MyPassword
$objNetwork = CreateObject("WScript.Network")
$strComputer = $objNetwork.ComputerName
$objComputer = GetObject("winmgmts:{impersonationLevel=Impersonate}!\\.\root\cimv2:Win32_ComputerSystem.Name='"+@wksta+"'")
$ReturnValue = $objComputer.JoinDomainOrWorkGroup("MyDomain.com", $password, "MyDomain\"+$user, $OU, 4)
If $ReturnValue
	? "Failed removing "+@WKSTA+" from domain"
	? "ReturnValue = " + $ReturnValue
		GoTo END
EndIf


I'm obviously missing a step, or something. Any help would be appreciated.
Thx.