Navigate with the Windows explorer to the directory/ file which contains your confidential data

Right click on the directory/file and choose properties from the menu

Select the Security tab and click on the button Advanced

Select the Auditing tab and click on the button Edit

Click on the button Add

Type everyone and click on Check Names after that click on OK

Mark both the columns Successful and Failed in the following lines:

- List folder / read data

- Create files / write data

- Delete subfolders and files

- Delete

Click on OK.

Click on Apply. If there are a lot of files this may take some time.

After the Apply is finished click on OK in this window and in all the previous windows.