If you have HP EliteBook 8770w do:

Shutdown your mobile workstation.

Push startup button

push ESC key

push F10 to open BIOS setup

With left arrow go to System Configuration

down to :

Device Configuration

down to :

Virtualization Technology (VT-x)

Press Enter to check

Press F10 to save

Select Yes

http://h30434.www3.hp.com/t5/Other-Notebook-PC-Questions/activating-vt-x-from-bios/td-p/260444/page/2