The header is a "block of information about file content". To access the file header you need to open the "XLS" file as a binary file. The information about password, format, version,... are in the header of file.
I need a routine to locate, in the XLS file header, the string generated by the password entered by the user in an excel spreadsheet.
I want to use the string generated by the user's password to encrypt data in a database that will be manipulated by the excel.
If possible, for 2003 and 2010...