BitLocker Automatic lock is not working

I turned on BitLocker to one of my partitions. I wanted an Auto Lock option, for which I tweaked the registry. The following is the code, which I actually found in the EightForums.
 Windows Registry Editor Version 5.00                                                                                       
; Created by: Shawn Brink
; http://www.eightforums.com
; Tutorial: http://www.eightforums.com/tutorials/21325-lock-drive-add-context-menu-bitlocker-drives.html
[HKEY_CLASSES_ROOT\Drive\shell\lock-bde]
"AppliesTo"="System.Volume.BitLockerProtection:=1 OR System.Volume.BitLockerProtection:=3 OR System.Volume.BitLockerProtection:=5 NOT C:"
@="Lock Drive..."
"HasLUAShield"=""
"MultiSelectModel"="Single"
[HKEY_CLASSES_ROOT\Drive\shell\lock-bde\command]
@=hex(2):77,00,73,00,63,00,72,00,69,00,70,00,74,00,2e,00,65,00,78,00,65,00,20,\
  00,6c,00,6f,00,63,00,6b,00,2d,00,62,00,64,00,65,00,2e,00,76,00,62,00,73,00,\
  20,00,25,00,31,00,00,00
I added the above code to the registry. You can see the screen shot below.

And, I also pasted a .vbs file with the following code in the System32 folder.
' Created by: Shawn Brink
' http://www.eightforums.com
' Tutorial: http://www.eightforums.com/tutorials/21325-lock-drive-add-context-menu-bitlocker-drives.html
Drive = ""
Last = Wscript.Arguments.Count - 1
For n = 0 To Last
 Drive = Drive & " " & Wscript.Arguments.Item(n)
Next
Drive = Replace(Drive,":\",":")
CreateObject("Shell.Application").ShellExecute "manage-bde.exe", "-lock -forcedismount " & Drive, "", "runas", 0
Then, I got a LockDrive option in the right-click menu which helped me to lock the drive without rebooting. (As shown in the following screenshot).

The option worked properly for a few days and now, when I click on "LockDrive", it is not working.
How to repair this tweak and make the "LockDrive" option in the right-click menu work properly?
I am running Windows 8.1 Pro x64.

Published By
S.G.Godwin Dinesh.MCA
Sr.System Administrator