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I downgraded from Windows 10 to 8.1 the other day and after rebooting I got the error message below. ‘Recovery Your PC needs to be repaired The boot configuration date for your PC is missing or contains errors File \EFI\Microsoft\Boot\BCD Error code: 0xc000000f I have tried 8.1 installation media via USB as my Vaio doesn’t have an optical drive and each time I got in to it I get that blue screen and when I press refresh or re-install it says “The drive where Windows is installed is locked.Unlock the drive and try again.” What can I do to resolve this? I have tried check disk, tried bootrec but nothing works, any help would be gratefully appreciated. (If the hard drive needs replacing, what would I need and where do I get it from?)
Check here this might help: http://www.tomsguide.com/forum/id-185218…
Pointers to be focus when you encounter this error. Corrupt boot sector due to power outages, virus/malware infection.Damaged hard disk due to power outages. Corrupt system files due to improper shutdown and/or power outage. Damaged Hardware Check this website for Solutions https://www.errorsolutions.tech/error/er…
