A record of all of the files on a hard drive partition are kept in a record called master file table. When deleted using the normal operating system tools, the record of the files are removed from this table. But this still leaves the file data on the hard drive. Using specialized tools like Recuva, these deleted files can be recovered easily.
One way to ensure that all data belonging to the deleted files is completely destroyed is through an application that can erase the free space. This can easily be achieved using a freeware tool like Free Space Wipe. This tool is a portable program for Windows that can overwrite all the free space available on a hard drive and thereby destroying all the remnants of any deleted files.
The user interface of Free Space Wipe allows you to select one of the target drives (partitions) visible to the Windows. If your hard drive contains a Linux partition (with file system like ext4) then it won’t be visible to Free Space Wipe. You should be very careful when selecting the target drive because all the free space on that drive will be wiped – eliminating all the possibility of file recovery from that drive.
From the wipe type methods, you can choose to overwrite with 1’s only, with 0’s only or with blocks of binary data. You can also choose to keep overwriting once it has finished and can cycle it many times. As you click on the Start button, it will do its job and a progress bar will indicate the progress of overwriting the free space.
Free Space Wipe is a great little tool that is helpful when you want to completely destroy all the file contents of the files that you have already deleted using File Explorer in Windows or any other program without using a secure file shredder.
You can download Free Space Wipe from https://www.michaelburns.net/Software/FSWipe/.