VBS ConvertToXlsx

Sub ConvertToXlsx()
    Dim fso As Object
    Dim fld As Object
    Dim strPath As String
 
    Set fso = CreateObject("Scripting.FileSystemObject")
    ' Specify the folder
    strPath = "d:\Test"
    Set fld = fso.GetFolder(strPath)
    Call ProcessFolder(fld)
End Sub
 
Sub ProcessFolder(fld As Object)
    Dim sfl As Object
    Dim fil As Object
    Dim wbk As Workbook
 
    ' Loop through the files
    For Each fil In fld.Files
        If Right(fil.Name, 3) = "xls" Then
            Set wbk = Workbooks.Open(fil)
            If wbk.HasVBProject Then
                wbk.SaveAs fil & "m", 52
            Else
                wbk.SaveAs fil & "x", 51
            End If
            wbk.Close False
        End If
    Next
 
    ' Loop through the subfolders
    For Each sfl In fld.SubFolders
        ' Call ProcessFolder recursively
        Call ProcessFolder(sfl)
    Next
End Sub