I have password protected two files now in Excel 2007. After opening and then saving a few times, the file becomes corrupted and I cannot open. The following error message appears "Excel cannot open the file"XXXX.xlsx" because the file format or file extenson is not valid. Verify that the file has not been corrupted and that the file extension matches the format of the file.
The files that I created contains sensitive information and I really need to get to them.l