When you delete files on a computer, they are put in the trash and then, when it empties, they are deleted. Whenever data is deleted it is not completely removed from the disk but only the references are removed to find it. Without going into the technician, just know that a data on the disk is permanently deleted only if it is rewritten with another file otherwise, even if it is no longer on the PC, it can still be recovered with external programs. It so happens that, in theory, every data and every deleted file can be recovered from the computer.
Conversely, there are also programs to permanently delete all files so that they are no longer recoverable. Just to give a trivial example, you can think of the computer as if it were a piece of written paper, if you delete the word with a line, it is still legible but if you delete 50 lines or if you write on it, here we no longer read.
In this guide, therefore, we see two different things for Windows 10, 8.1 and Windows 7 : how to delete the free space and how to clean the disk from unnecessary files in a more or less complete way, always without external programs .
First of all, let's see the advanced disk cleaning that you can get on Windows as a Microsoft help page explains.
The disk cleanup I am talking about is the classic default one present on every Windows computer, both Windows 7 and Windows 8.1 and Windows 10. If you open the computer resources and press the right mouse button on the icon of a hard disk, in the general tab that shows the space used, there is the " Disk Cleanup " button. If you press it you can choose which objects to delete from the computer among the temporary files, those of the recycle bin and other superfluous files.
NOTE: Disk Cleanup in My Computer has been removed in Windows 10 since 2018.
You can launch disk cleaning (also in Windows 10) by pressing the right mouse button on the Start button, then going to Run and writing the cleanmgr / sageset: 50 command . Press on System File Cleaner to do complete removal of unnecessary files.
In Windows 10 you can do disk cleaning by going to Settings> System> Storage and press the Configure memory sensor link or run it now . On the next screen, scroll down to find the Clean Now button, under the Free up space now section. If you select the option Delete previous versions of Windows before cleaning, then the installation files of the various updates will be deleted.
The options of the Memory sensor screen can then be used to do disk cleaning automatically, in order, as already explained, to keep free space in Windows 10. You can then make sure that temporary files, the Recycle Bin and also the files saved in the download folder are automatically deleted from the system after a certain period of time.
In Windows 10 and also in Windows 7 and Windows 8 there is still a way to widen these options and enable advanced disk cleaning that is more complete and therefore frees up more space. To do this you must create a new shortcut on the desktop by right-clicking on a point on the screen and giving the following command line as a path:
% SystemRoot% \ System32 \ Cmd.exe / c Cleanmgr / sageset: 65535 & Cleanmgr / sagerun: 65535
This link opens the same utility with many more options for complete cleaning related to deleting some system files, log files, user files, log files and other things. If you want to give an icon suitable for the connection, you can press the change icon button and give this % windir% \ system32 \ cleanmgr.exe as the path.
To clean the disk there are also other programs to recover space on the hard disk by eliminating unnecessary files.
Among these, an excellent software is Moo0 Disk Cleaner, a portable program that does not require installation capable of deleting, from a beautiful graphical interface, all temporary files, caches, traces of use of programs and all superfluous files that are not they serve.
Still with reference to disk cleaning, on Windows 10, 7 and 8, it is possible to launch a command that cleans up the free and unused space so as to completely reset it and prevent the previously deleted files from being recovered .
Follow the guide to overwrite the free space in Windows .
If you prefer, you can use other programs to delete files safely and permanently.
To delete temporary and useless files, I recommend Ccleaner and Ninja System instead.
