VirtualBox VERR_VMX_NO_VMX

Question

I downloaded VirtualBox, knowing that my computer has VT-X, and I just created two VMs, but when I started them, I saw this error:

_{VirtualBox - Error}
Failed to start the virtual machine Android.
_(Details)
VT-x is not available (VERR_VMX_NO_VMX).

Result Code: E_FAIL (0x80004005)
Component:  ConsoleWrap
Interface:   IConsole {872da645-4a9b-1727-bee2-5585105b9eed}

 ^{[Manually transcribed]}

I have previously run VirtualBox on this PC flawlessly.  Why am I getting this error now?  How can I get VirtualBox to work?

Solution

Thank you Hrobky, this was helpful. At an ASUS i7 with a UEFI BIOS that does not allow to disable safe boot, on a Windows 10 without encryption, it was enough these 2 steps from your solution:

start->GPedit

Computer Config > Admin Templates > System > Device Guard > 
Virtualization Based Security: Disabled

admin cmd:  bcdedit /set hypervisorlaunchtype off 

then reboot

with change these setting at BIOS

Boot / Launch CSM : Enable

Boot / Launch CSM / Boot Device Control : UEFI and Legacy OPROM

Boot / Fast Boot : Disabled

Boot / OS Type : Other OS

Comments

[Ramhound]

You have installed software that isn’t compatible with Vbox. You will have to identify that software. Information provided doesn’t allow us to do that for you

[Ramhound]

Possible duplicate of Enable VX-T on Dell Precision Tower 3620

[Ramhound]

Another possible duplicate: superuser.com/questions/601572/…

[JustAnotherBitcoin]

I have used Windows 10 and 7 to also with this issue

[Ramhound]

Possible duplicate of VT-x is not available, but is enabled in BIOS

[Hrobky]

This would make 64-bit guest machine unable to run.

[Hrobky]

Please list your CPU model and Windows version. AFAIK Intel 8xxx are not affected anymore. There may be a great progress since Win10 1703.

[fometeo]

CPU model Intel i7-7700 on an ASUS motherboard Prime B250M-K Windows 10 full update at the date, sorry I do not have record of the build.

[fa wildchild]

First step is working for me. Dell E5570 i7 Windows 10 2004