Could not start 2CPU Guest - missing VT-x

[KFlash]

Hi,

When I try to start my 2CPU Guest this error shows up:

VT-x features locked or unavailable in MSR. (VERR_VMX_MSR_LOCKED_OR_DISABLED).

Fehlercode:E_FAIL (0x80004005)
Komponente:Console
Interface:IConsole {db7ab4ca-2a3f-4183-9243-c1208da92392}

How do I corretly enable VT-x so that I can start my guest with more than 1 CPU.

HOST:
ThinPad W500 (Type 4061-3DG)
CPU: Intel Core Duo CPU T9400
OS: WinXP SP3
VT-x enabled in BIOS

GUEST:
Xubuntu
VM Settings: 2CPUs, 90% MaxLoad, VT-x + Nested-Paging enabled.

[mpack]

The error message says that VT-x is disabled, or something else is using it - I can't tell you what. I'd tell you to double check the BIOS, but really this is pointless: your CPU is only a dual core, you can't usefully assign both cores to the guest. What would the host run on?

[TheLostOne]

I got the same error when starting a Ubuntu Server 12.04 machine.
The problem started after the latest Virtualbox update.

My other Windows guests with VT-x enabled start without an issue.

Edit:
Forget my post.
VT was really disabled in my BIOS. I don't know why this could have happened. I didn't change anything and the VM was working before the VB update.