Start Microsoft Office Excel and on the File menu click Open. Select the corrupted file and choose Open and Repair from the drop-down list associated with the Open button. If Microsoft Office Excel cannot open the file, choose Extract Data. If you receive a message which says that the file caused a serious error the last time it was opened, agree to continue opening it. Save the recovered workbook.
Another solution can be saving the file in HTML format. On the File menu, click Save as, select Web Page and check Entire Workbook box. Then click on Save button and Close the file. Right click on the file and select Open with > Microsoft Office Excel. On the File menu, click Save As and in the Save as type list, select Microsoft Excel Workbook. Change the name of the file and click Save.
On the Microsoft support web page you can find more solutions, explained step by step, to recover a corrupted Microsoft Office Excel file.