Vagrant up - VBoxManage.exe error: VT-x is not available (VERR_VMX_NO_VMX) code E_FAIL (0x80004005) gui headless

Stop hyper-v service running by default in Windows 8/10, since it blocks all other calls to VT hardware.

Additional explanation here: https://social.technet.microsoft.com/Forums/windows/en-US/118561b9-7155-46e3-a874-6a38b35c67fd/hyperv-disables-vtx-for-other-hypervisors?forum=w8itprogeneral

Also as you have mentioned, if not already enabled, turn on Intel VT virtualization in BIOS settings and restart the machine.

---

To turn Hypervisor off, run this from Command Prompt (Admin) (Windows+X):

bcdedit /set hypervisorlaunchtype off

and reboot your computer. To turn it back on again, run:

bcdedit /set hypervisorlaunchtype on

If you receive "The integer data is not valid as specified", try:

bcdedit /set hypervisorlaunchtype auto

-- credit Tj Kellie

I just solved this problem by disabling(uncheck) Hyper-V. Seems Hyper-V was enabled when I installed Docker

Control Panel -> Program And Features -> Turn Windows Features on or off.

You may need to reboot afterwords.

Warning: Vagrant with VirtualBox cannot work with Docker at the same time.

Although this is an old question, but I've still encounter it recently.

This is what worked for me on my i7-3770 3.40GHz, Z77 extreme motherboard running Windows 10.

In Windows, disable Hyper-V:

1. Open up a PowerShell or CMD session as Administrator.
2. Type the following command: dism.exe /Online /Disable-Feature:Microsoft-Hyper-V-All
3. Windows will ask you to restart.

In the bios:

1. Disable >>> Intel Virtualization Technology, vt-d
2. Save the bios settings and allow it to restart and boot into Windows.
3. Shutdown the computer (I've tried just restarting and it didn't work)
4. Power up the computer, go into the bios and re-enable the above disabled settings.
5. Save, restart.

Download the Intel Utility to check.

You should now see it been supported:

If it still doesn't work, try re-enabling Hyper-V first then following the steps above.