By default windows will store your activity history like when and what file or application you have opened and show in task view. This is helpful if you want to go back in past also troublesome if your machine is used by others, for disabling please follow the below steps: Go to Windows setting by pressing window button + i, or from start menu click on setting icon. From setting window search for Activity history privacy settings. From the Activity History setting uncheck the Store my activity history on this device and from below click on Clear button it will remove the previous history. All Done.