Error that i received while attempting to run Windows 8 ISO on VirtualBox before i could buy Windows 8 Pro. This happened with both 64 bit and 32 bit installations.
VT-x/AMD-V hardware acceleration has been enabled, but is not operational. Certain guests (e.g. OS/2 and QNX) require this feature.
Please ensure that you have enabled VT-x/AMD-V properly in the BIOS of your host computer.
Later i tried to run Ubuntu 12.0 64 Bit but it failed to run with error
This kernel requires a x86-64 cpu but only detected an i686 CPU. Unable to boot – please use a kernel appropriate for your CPU
It was caused as the VM was by default set to “Enable VT-x / AMD-V” Hardware Virtualization. This setting is visible by clicking on VM then Right Click > Settings > System > Acceleration

3 responses to “AMD-V hardware acceleration has been enabled, but is not operational VirtualBox”
Here is how you resolve the issue:
Can access the Startup Menu by pressing “ESC” key during boot up sequence. Must do it quickly or Windows will launch.
Press F-10 to access BIOS Setup
Select the Configurations Tab
Select Device Configurations
Check the Virtualization Technology Box
Save and Exit
Exit Startup Menu
MrAlone,
I have a HP Compaq dc7800p SFF and had the same problem when trying to install WS2008 R2 on Virtualbox on my hosted machine with Win7 Enterprise x64 bit
Solution was to enable Virtualization Technology Box in BIOS.
Thnx 🙂
frend hlep in my virtual box i set by intruction you but this problem this same problem what i do