Hi,
It seems that BITS service is stopped from running. Refer this article to make sure all Windows Update services are running and then try installing the update and check.
"Windows Update Cannot Check For Updates" error message when you try to install updates
http://support.microsoft.com/kb/2730071
For error “**The drive where windows is installed is locked. Unlock the drive and try again.”**Let’s try these steps and check if it helps.
- Boot up from your Windows 8 disc.
- Don't click 'Install Now', click Repair Your Computer.
- Click Advanced Options.
- Click Other Options.
- Click Diagnose my PC.
- Wait for your computer to reboot.
Your computer has now an unlocked hard drive.
You may also refer to the link and check if it helps.
http://social.technet.microsoft.com/Forums/en-US/fc3c93ae-95d8-4b26-a085-b2742674bc8f/cannot-unlock-drive-and-unable-boot-back-into-windows-8?forum=W8ITProPreRel
Note: Modifying BIOS/complementary metal oxide semiconductor (CMOS) settings incorrectly can cause serious problems that may prevent your computer from booting properly. Microsoft cannot guarantee that any problems resulting from the configuring
of BIOS/CMOS settings can be solved. Modifications of the settings are at your own risk.
Hope it helps.