I got this error:

Failed to open a session for the virtual machine win7.
VT-x is disabled in the BIOS for all CPU modes (VERR_VMX_MSR_ALL_VMX_DISABLED).
Result Code: NS_ERROR_FAILURE (0x80004005)
Component: ConsoleWrap
Interface: IConsole {872da645-4a9b-1727-bee2-5585105b9eed}

I run it before. but when I again start it, I got that error!!!

this is my system situation:

  • Ubuntu 18 on my computer (64b)
  • windows 7 on my VirtualBox
  • in VirtualBox PAN/NX is Enable
  • in Bios Virtualization Technology is Enable (Bellow picture)
  • allocated RAM to VirtualBox is 2048 MB

this is answer of sudo kvm-ok:

INFO: /dev/kvm does not exist
HINT:   sudo modprobe kvm_intel
INFO: Your CPU supports KVM extensions
INFO: KVM (vmx) is disabled by your BIOS
HINT: Enter your BIOS setup and enable Virtualization Technology (VT),
  and then hard poweroff/poweron your system
KVM acceleration can NOT be used

enter image description here

  • 2
    The message is explicit. You need to enable virtulzation in your BIOS. bce.berkeley.edu/enabling-virtualization-in-your-pc-bios.html or similar
    – Panther
    Jul 28, 2018 at 5:42
  • What does mean this in that link @Panther : Delete any existing VMs (Machine > Remove ** and select ** Delete all files) and re-import the .ova file
    – parvij
    Jul 28, 2018 at 5:50
  • 1
    You need to enable virtulzation in your BIOS. I did not tell you to delete anything. Google search your bios
    – Panther
    Jul 28, 2018 at 5:58
  • Yes it should work now
    – Panther
    Jul 28, 2018 at 13:48
  • 4
    If you are still getting the same error message it is a hardware problem or misconfigured BIOS settings. You can not fix this from ubuntu
    – Panther
    Jul 30, 2018 at 14:30

1 Answer 1


when I wanted to enable virtualization, I reset my computer and do it. It does not work. Today I notice that "sudo kvm-ok" said, "poweroff/poweron your system". I try this instead of restarting and it works!!!!

I didn't think maybe restart being different from poweroff/poweron!!!!

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