In this case, the document needs to be saved in the .xls format. Here’s how you can save the file to ensure backward
compatibility:
When saving a worksheet for the first time by pressing [Ctrl] + [S], you will be taken to the ‘Save As’ dialog box. If the
file is already saved, simply click on the MS Office button and then go to ‘Save As | Excel 97-2003 Workbook’ to open this dialog box.
In the ‘File Name’ field, enter the name of the file and then use the ‘Save as type:’ dropdown list to select the option
‘Excel 97-2003 Workbook (*.xls)’.
Click ‘OK’.