Boot menu (setup menu /BIOS) for Lenovo E431 not accessible

I am struggling to get the boot/BIOS menu for my Lenovo E431 laptop. I tried Esc, F1, F2, F3, F4, F5, F8, F9 F10, F12 and Del, but all failed. The Lenovo docs: http://www.lenovo.com/shop/americas/content/user_guides/e431_e531_ug_en.pdf says to use F1, but that doesn't work.

Could anybody help me to get into BIOS or suggest a workaround for enabling VT-x (VERR_VMX_MSR_VMXON_DISABLED error) while trying to setup a virtual box on Oracle VM.

If you're running Windows8, the operating system now controls access to the EUFI, which is a new specification meant to replace the BIOS interface.

In 64-bit Windows 7 (perhaps 32-bit also?), the OS can tell the motherboard to hide the boot/bios menu settings. One reason it will do so is if you Hibernate your system, instead of shutting it down.

I just had this happen to me; very frustrating! I let windows recover from Hibernation, then shut it down using "Shutdown", and then my bios/boot options came back.

Good luck!