I am trying to set the application.calculation property in an embedded excel workbook object in a powerpoint file using a powerpoint vba macro. With the code below I am receiving the error:

'Unable to set the Calculation property of the Application class'

This would really help performance if I can get this to work. 

Public oPres As Object
Public osld As Object
Public oshp As Object
Public total As Integer
Public count As Long
Public oxlbook As Object
Public oxlapp As Object
Public oxlchtsht As Object
Public oxldatsht As Object
Public oxlqrysht As Object
Public oxlqt As Object
--------------------------------------------------------------
Public Sub update_ppt()

Set oPres = ActivePresentation
total = ActivePresentation.Slides.count
count = 0
sttime = Now
progressForm.Show

    With oPres
        For Each osld In .Slides
            count = count + 1
        
            Call chtupdate(osld)
            
            Call UpdateProgress
        Next osld
    
    End With
progressForm.Hide

endtime = Now
elptime = (sttime - endtime)
tottime = Format(elptime, "nn:ss")
msg = "Update Done" & vbCrLf & vbCrLf
msg = msg & "Elapsed Time: " & tottime
MsgBox msg

End Sub
-----------------------------------------------------------
Private Sub chtupdate(oSlide As Object)
    
For Each oshp In oSlide.Shapes
    If oshp.Type = msoEmbeddedOLEObject Then
        Set oxlbook = oshp.OLEFormat.Object
        Set oxlchtsht = oxlbook.Worksheets("charts")
        Set oxldatsht = oxlbook.Worksheets("data")
        Set oxlqrysht = oxlbook.Worksheets("query")

        oxlbook.Application.Calculation = xlCalculationManual

        For Each oxlqt In oxlqrysht.QueryTables
            oxlqt.Refresh BackgroundQuery:=False
        Next oxlqt

        oxlbook.Application.Calculation = xlCalculationAutomatic

        DoEvents

    End If

    Set oxlqt = Nothing
    Set oxlbook = Nothing
        
    Next oshp

End Sub
Thanks

Erick