Run it in Safe Mode. To do this reboot and keep tapping the F8 key just before the Windows screen loads. Then select Safe Mode from the menu that should appear.
This stops a lot of things from running that would interfere with Scandisk.
Best phone camera 2017
Stunning new film posters by Hattie Stewart, Joe Cruz & more
iPad Pro 10.5in (2017) review
28 astuces pour profiter au mieux de votre iPhone