Can't repair Windows 8.1, hard drive locked.

Dear TSG

I'm using a Lenovo Ideacentre B340 running windows 8.1 with the following spec:

Intel Pentium CPU G645 @ 2.90GHz
DDR3 SDRAM
Lenovo Mahobay motherboard
440GB Hard Drive

My system crashed yesterday during a windows update. I can't boot to safe mode or use system restore.

I tried a "refresh" but it says "The drive where Windows is installed is locked. Unlock the drive and try again. I do not have a back up disk.

Any advice would be greatly appreciated.

Best Regards

Pyxidium