The simplest method is to create a text file (Notepad) with the following content and saving it with a .cmd extension on your desktop.
manage-bde -lock volume: -fd
-fd: ForcedDismount, use this parameter to lock the volume even if it's in use.
The above example image will lock volume E:
To lock the volume right click the .cmd file you created and run it with Administrator privilege (If UAC (User Account Control) is set to Always Notify.
This method is to avoid launching the Windows Command Processor (cmd.exe) and typing the command and hence saves time required to lock the volume.
To learn more about parameters for manage-bde command visit the following link,
http://technet.microsoft.com/en-us/library/dd875513(WS.10).aspx
