title: drop down list compatibility issue between Excel 2007 and Excel 2010
body: <p>I prepared a spreadsheet where I used the drop down list command in several cells (data validation, list).  I needed to provide two versions of the same spreadsheet: one saved as Excel 2007 file, and the other one as Excel 2010 file.  </p>
  
  <p>If I open the Excel 2007 file with Excel 2010, in the cells where I inserted the drop down list, the reference to the cells that contain the list is somehow changed and the drop down list shows the wrong data. </p>
  
  <p>For example, if I specify to use as the data in the list the values of cells C20:C25, when I open the file with Excel 2010 the cells are changed to D15:D20.  I did not find a trend in the "shifting" of the referenced cells.</p>
  
  <p>How do I prevent this without using Excel 2007 for the 2007 file only and Excel 2010 for the 2010 file only?</p>