New
#21
Check if fast startup is disabled, in many cases (if not all) it needs to be disabled.
Fast Startup - Turn On or Off in Windows 10 - Windows 10 Forums
Then you may also need to change a setting in the BIOS in 'BIOS Features' > 'Windows 8', I'm not sure which one but if it is necessary and disabling fast startup isn't enough then the boot mode needs to be changed to legacy.