Beginning with Crystal Ball 7.3.x, Crystal Ball stores its data in a new format within Microsoft Excel 2007 or later files. Older Crystal Ball data formats are converted to the new format the first time you perform a Save or Save As command in Microsoft Excel 2007 or later. Crystal Ball must be loaded when you save the file.
Before converting older XLS files to one of the new Microsoft Excel 2007 or later formats, Oracle recommends that you keep backup copies of your older workbooks for safekeeping.