Unprotect Excel 2013 spreadsheets

On this site we previously posted the solution to decrypt spreadsheets for the old Excel version, and it has been one of the most relevant posts to this day.

However, the new versions of Excel, in XLSX file formats, have another feature, very simple to be manipulated.

Basically, see the steps:

1. Rename the file to ".zip" extension, and open the file with a common decompressor, from the windows itself.

2. Look for the XML file that contains the name of the spreadsheet, each spreadsheet has a unique XML with the data for it.

3. Look in this XML, where the protection line is, where the value of sha256 and salt are.

4. Create a new document with the protected spreadsheet, enter the desired password and save this new file and also open it as a compressed file, and look for sha256 and salt (that you know the password) and replace it leaving the same in the another XML file.

5. Save the ZIP file, rename it to XLSX and use your known password.

See below the video of how to perform the procedure.