Possible your software was corrupted if so advise use-excel recovery,as how as i know tool is freeware,application may try to open the necessary *.xls, *,xlt, *.xlsx, xlsm, *.xltm, *.xltx, *.xlam file and see an error message on the screen instead of it: Microsoft Excel unable to read file, This file is not in a recognizable format, etc,recover after attack viruses, problems with media (a hard drive failure, a corrupted CD or DVD, etc.), errors in transferring the file via the LAN or the Internet, etc,extract information from corrupted Microsoft Excel files,can filter files of the *.xls, *,xlt, *.xlsx, xlsm, *.xltm, *.xltx, *.xlam formats,will display a dialog box with the question whether this worksheet should actually be scanned,allows you to view the entire information in a convenient form and to make sure that the tool reproduced it correctly,exporting information recovered from the corrupted worksheet into Microsoft Excel.