If you are using Excel 2007, you may have saved your original Rental Workbook as an Excel 2007 file type (e.g. WorkbookName.xlsx)
In order that the Rental Workbook is compatible with most versions of Excel, we use the Excel 97-2003 file type (e.g. WorkbookName.xls)The Upgrade and Renewal programs both need to see an Excel 97-2003 workbook file, as the two file types are incompatible, so we advise in our User Guide to save your Rental Workbook as an Excel 97-2003 file.
To do this:
Open your existing Rental Workbook
Click the Office Button
Select Save As
Choose Excel 97-2003 workbook
Close your Rental Workbook and then run through the Upgrade or Renewal process again. This time you should see your Rental Workbook as an option.