Our hardware vendor has sold us a laptop that comes with Windows 7 Pro OEM. Since we want Windows 7 Enterprise (for features like DirectAccess and BitLocker), the vendor has supplied us with a Software Assurance only license to upgrade OEM Win 7 Pro to Win 7 Ent. Do I need to install Windows 7 Enterprise Volume License media and re-install Windows, or is there a process to turn this existing Windows 7 Pro install into an "Enterprise" ?