Hi!
Try!
Go to "File menu" ---->open and select your corrupted file. Then u will
notice that below at "Open" a dropdown sign appear. Expand it and select
"Open and repair".
You can repair your excel and word file with the steps given by Sheryakhan.
If you are not able to fix the problem than you should use Excel repair
software to fix the problem. You can download it from http://www.repair-excel-file.com/download-xls-repair-software.php