Another way that should work: right-click the mini power icon on one end of your taskbar. Select Power Options. This will open a window with power settings in Control Panel. Select a plan. (with the newest w10 there should just be one unless you have a custom because it is programmed to be adjustable (balanced)). Click change lan settings then click change advanced power settings. In the new power settings popup expand hard disk and then expand turn off hard disk after and click the down arrow until it says "Never" do this for both battery and when plugged in. this is the solution i found after reading the original answer to this issue.