Macro works great in 2007 but not in older excel format

Macro works great in 2007 created from a expert in this forum. One associate I work with uses a older excel format 98 I believe and willl not upgrade??.

The code below errors when promting the user here

 With Application.FileDialog(msoFileDialogOpen)

I also would bet it would error elsewhere too. Is there anyone that could help out converting this code to the earlier version.

Option Explicit
Private Sub Workbook_Open() 
    Dim wb1 As Workbook, wb2 As Workbook
    Dim cell As Range, counter As Long
    
    ' Prompt user to select a file1
    With Application.FileDialog(msoFileDialogOpen)
        .InitialFileName = ThisWorkbook.Path              ' Default path
        .FilterIndex = 3
        .Title = "Please Select a File"
        .ButtonName = "Open"
        .AllowMultiSelect = False
        .Show
        If .SelectedItems.Count = 0 Then Exit Sub   ' User clicked cancel
        Set wb1 = Workbooks.Open(Filename:=.SelectedItems(1))
    End With
    
    ' Prompt user to select a file2
    With Application.FileDialog(msoFileDialogOpen)
        .InitialFileName = ThisWorkbook.Path              ' Default path
        .FilterIndex = 3
        .Title = "Please Select a File"
        .ButtonName = "Open"
        .AllowMultiSelect = False
        .Show
        If .SelectedItems.Count = 0 Then Exit Sub   ' User clicked cancel
        Set wb2 = Workbooks.Open(Filename:=.SelectedItems(1))
    End With
    
    For Each cell In wb1.Sheets(1).Range("E11:H25")
        If Not IsEmpty(cell) Then
            If cell.Value = wb2.Sheets(1).Range(cell.Address).Value Then
                cell.Interior.Color = vbYellow
                wb2.Sheets(1).Range(cell.Address).Interior.Color = vbYellow
                counter = counter + 1
            End If
        End If
    Next cell
    
    MsgBox counter & " Duplicates Highlighted", vbInformation, "Comparison Complete"
   Me.Close True
Debug.Print
End Sub

Thanks, Tom