title: Python and Excel: Overwriting an existing file always prompts, despite XlSaveConflictResolution value
body: <p>I'm using the Excel.Application COM object from a Python program to open a CSV file and save it as an Excel workbook.  If the target file already exists, then I am prompted with this message: "A file named '...' already exists in this location.  Do you want to replace it?"  That message comes up despite the fact that I have set the <a href="http://msdn.microsoft.com/en-us/library/microsoft.office.interop.excel.xlsaveconflictresolution.aspx" rel="noreferrer">XlSaveConflictResolution</a> value to xlLocalSessionChanges, which is supposed to automatically overwrite the changes without prompting -- or so I thought.</p>
  
  <p>I'm using Microsoft Office Excel 2007 (12.0.6535.5002) SP2 MSO and ActivePython 2.6.5.14.  I have tried all three of the XlSaveConflictResolution values using both constants and integers.  I have not tried different versions of Excel.</p>
  
  <p>Here's a code snippet:</p>
  
  <pre><code>import win32com.client
  xl = win32com.client.gencache.EnsureDispatch("Excel.Application")
  wb = xl.Workbooks.Open(r"C:\somefile.csv")
  wb.SaveAs(r"C:\somefile.xls", win32com.client.constants.xlWorkbookNormal, \
      None, None, False, False, win32com.client.constants.xlNoChange, \
      win32com.client.constants.xlLocalSessionChanges)
  </code></pre>
  
  <p>And here's the spec from Microsoft about the SaveAs method for an Excel workbook object: <a href="http://msdn.microsoft.com/en-us/library/microsoft.office.tools.excel.workbook.saveas(VS.80).aspx" rel="noreferrer">http://msdn.microsoft.com/en-us/library/microsoft.office.tools.excel.workbook.saveas(VS.80).aspx</a></p>
  
  <p>Could this be a new "feature" in Excel 2007, or did I just do something wrong?</p>