AD useraccountcontrol property update.

ADuserAccountEntry.Properties[uac].Value = ""
ADuserAccountEntry.Properties[uac].CommitChanges()

ADuserAccountEntry.Properties[uac].Value = new value
ADuserAccountEntry.Properties[uac].CommitChanges


i.e. Delete the old value and then add the new value.. i.e. update. An overwrite is not allowed.