Outlook - Termin-Erstelung per VBS funktioniert nicht

Dim objArgs, olkApp, olkNS, olkAppointment
Set objArgs = WScript.Arguments
If objArgs.Count > 0 Then
    Set olkApp = CreateObject("Outlook.Application")  
    Set olkNS = olkApp.GetNamespace("MAPI")  
    olkNS.Logon "Outlook"  
    Set olkAppointment = olkApp.CreateItem(1)
    For I = 0 to objArgs.Count - 1
          Select Case LCase(Mid(objArgs(I),1,3))
                Case "/s:"      'Subject  
                      olkAppointment.Subject = Mid(objArgs(I),4)
                Case "/l:"      'Location  
                      olkAppointment.Location = Mid(objArgs(I),4)
                Case "/t:"      'Start time  
                    olkAppointment.Start = Mid(objArgs(I),4)
                Case "/e:"      'End time  
                      olkAppointment.End = Mid(objArgs(I),4)
                Case "/a:"      'All day event  
                      olkAppointment.AllDayEvent = Mid(objArgs(I),4)
                Case "/r:"      'Reminder set  
                      olkAppointment.ReminderSet = BooleanValue(Mid(objArgs(I),4))
                Case "/b:"      'Body  
                      olkAppointment.Body = Mid(objArgs(I),4)
          End select
    Next
    olkAppointment.Display
End If
Set objArgs = Nothing
Set olNS = Nothing
Set olApp = Nothing
WScript.Quit

Function BooleanValue(varValue)
      Select Case varValue
            Case "True","true", "T", "t"  
                  BooleanValue = True
            Case "False", "false", "F", "f"  
                  BooleanValue = False
            Case 0
                  BooleanValue = True
            Case 1
                  BooleanValue = False
      End Select
End Function