error 1004 when setting pivottable.pagefields
 

A code snippet:

Function FillYearMonth(ByVal theWorkbook As String, ByVal theWorkSheet
As String, _
ByVal thePivotTable As String, ByVal thePageField As String)
Dim ws As Worksheet
Set ws = Worksheets(theWorkSheet)
Dim pt As PivotTable
Set pt = ws.PivotTables(thePivotTable)
Dim pf As PivotField
Set pf = pt.PageFields(thePageField)
Dim lb As ListBox
Set lb = Worksheets(theWorkSheet).lstYearMonth
Call FillListBox(pf, lb)
End Function

I keep getting error 1004 after executing the line
Set pf = pt.PageFields(thePageField)


Can anyone point me what is wrong in this code?


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Amedee