Using windows 8 recovery disc or usb stick you can run repair commands to fix the boot record.
With bootrec.exe
bootrec /fixmbr
bootrec.exe /fixboot
bootrec.exe /RebuildBcd
as has been previously stated in this thread. I had to do it with a windows 10 install and it worked fine. Takes 5 minutes.
I had the same locked drive problem in windows 10. Using windows 10 install on a USB stick to boot the computer went into repair options and under advanced selected command prompt. I also found that 5 minutes doing the following worked. Note: my usb stick was x: and windows was identified on e...