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Sub SummarySheetPasteTest()
Dim RunNo As String, strPath As String, SourceFile As String
Dim wsWafer As Worksheet, WaferLetter As String, increment As Integer

Dim wsSummary as worksheet 
Set wsSummary = thisworkbook.sheets("summary")

RunNo = Mid(ThisWorkbook.Name, 6, 6)
Name = ThisWorkbook.Name
increment = 0

For Each wsWafer In Sheets(Array("XRD-A", "XRD-B", "XRD-C", "XRD-D", "XRD-E", "XRD-F", "XRD-G", "XRD-H", "XRD-I", "XRD-J"))
    
        WaferLetter = Chr(65 + increment)
        WaferRow = 21 + increment
        strPath = "C:\X'Pert Data\Wafers\W" & RunNo & "\WaferXRDAnalysis" & RunNo
        SourceFile = strPath
        If SourceFile <> "" Then
            Do
                'On Error Resume Next
                With Workbooks.Open(Filename:=SourceFile)
                    .Sheets(WaferLetter & "-G").Range("R2").Copy Destination:=wsSummary.Range("X" & WaferRow)
                    .Sheets(WaferLetter & "-G").Range("R4").Copy Destination:=wsSummary.Range("AA" & WaferRow)
                    .Sheets(WaferLetter & "-N").Range("R2").Copy Destination:=wsSummary.Range("AF" & WaferRow)
                    .Sheets(WaferLetter & "-N").Range("R4").Copy Destination:=wsSummary.Range("AH" & WaferRow)
                End With
                SourceFile = "StopThisLoop"
            Loop While SourceFile <> "StopThisLoop"
        End If
        increment = increment + 1
        'MsgBox "WaferLetter is " & WaferLetter
    Next wsWafer
End Sub