Hi,
You may try to rebuild the boot manager to unlock the drive and check.
a) After you boot your computer using Windows 8 DVD or System Repair Disc, a black screen appears with gray text "Press any key to boot from CD or DVD". Press any key.
b) Select the correct time and Keyboard type.
c) Click Repair your computer in the lower left corner.
d) Select Troubleshoot from Choose an option screen.
e) Click Advanced options in Troubleshoot screen.
f) Select Command Prompt.
g) Type Bootrec.exe, and then press ENTER.
e)****Type bootrec /RebuildBcd and then press ENTER.
After running the command restart the computer and try to perform a refresh booting form the Windows 8 disc.
How to restore, refresh, or reset your PC
Note: Apps you installed from websites and DVDs will be removed. Apps that came with your PC and apps you installed from the Windows Store will be reinstalled. Windows puts a list of removed apps on your desktop after refreshing your PC. When you perform Refresh or Reset of the PC, there are chances of losing data.
Hope the information helps. Let us know if you need further assistance with Windows related issues. We will be happy to help.