Whenever you switch from an older Windows version to Windows 10 or you install a major update on the system, a backup of the old Windows files is automatically created. This can unnecessarily use up space on your hard drive. — dpa
Whenever you switch from an older Windows version to Windows 10 or you install a major update on the system, a backup of the old Windows files is automatically created.
These are stored in a directory called windows.old. This backup may come in handy if errors occur during the transition, but it also takes up a lot of storage space. If you're sure that you no longer need the files, you can simply delete them to free up space.
First, go to the Explorer, then right-click on the hard disk containing the Windows installation (usually drive C:\). Under "Properties" you’ll find "Disk Cleanup" under the tab "General".
Then click on "Clean up system files" and check the box "Previous Windows installation(s)" in the following box. Clicking on "OK" starts the process of freeing up the storage space used for this purpose. — dpa
