Quickly open the DVD tray and pop in your Windows recovery disk or Windows installation disk in it. If you have created the recovery disk on a USB drive, then plug-in the USB drive. Repeatedly press the F12 key to bring up the menu that lets you select the boot device (it could be some other key for your system – check your system manual). You can fix these using your Windows recovery disk or installation disk. In order to fix these errors and continue to reset or refresh Windows, you will have to fix the BCD record and the MBR. These errors occur because the MBR or BCD records have become corrupt, perhaps because of power outage, system crash, malware infection or some other unknown reason. Some Windows 8 users have complained that when they try to Refresh or Reset Windows 8, it throws up an error saying the “A required drive partition is missing” or “Drive where Windows is installed is locked”.
