virtualbox.org

I give up.

::watching::

I enabled Hyper-V in a Windows 8.1 Enterprise machine and installed freshly downloaded Genymotion 2.5.2 from official source. It comes with VirtualBox 4.3.12.
At no point during Genymotion installation did I get a warning or error saying VT-x is required. Genymotion and VirtualBox both installed fine.
I set up a virtual device in Genymotion: Google Nexus 7 2013 with Android 5.1.0.
The OS type of the VM created in VirtualBox as a result is Other Linux (32-bit).

Genymotion seems happy to create devices without VT-x being available. The VM created is 32-bit.
I was not actually able to run the device because the graphics card of the host didn't support the correct OpenGL version, and I got an error message to that effect. However, I didn't get any error messages about VT-x or other virtualisation issues.

Seems to me the answer to the mystery is simply that 32-bit VMs are being used.
VirtualBox 5.0.0 probably just has some other, unrelated compatibility issue with Genymotion, that's why it's not working.

At least it's clear now thank you for the info

From the Genymotion site:

Genymotion cannot be run from a virtual machine. Indeed, it needs a direct access to the hardware in order to provide OpenGL acceleration. Running Genymotion from a virtual machine prevents it to directly access the hardware components. Therefore, Genymotion is incompatible when installed from VMWare, Parallels, Hyper-V or VirtualPC.

To run Genymotion virtual devices, you must install Oracle VM VirtualBox 4.1 or above. However, for performance reasons, we recommend using version 4.3.12.

Genymotion operation relies on the use of Oracle VM VirtualBox in the background. This enables virtualizing Android operating systems. If you do not already have Oracle VM VirtualBox installed on your computer, you will be asked to do so prior to installing Genymotion.

VT-x or AMD-V capable CPU, enabled in BIOS settings;

Please forgive my ignorance. I use VirtualBox solely for Genymotion, and know little under the hood. I will be happy to provide any information you guys need, but I need a bit instruction on how to produce the information if it is not obvious (e.g. logs).

@Hong - the bottom line is:
- There is no known way to run Hyper-V and VirtualBox both with VT-x on, so you shouldn't try.
- The only way to have VirtualBox run alongside Hyper-V is to have a 32 bits guest without VT-x enabled.
- Genymotion is supposed to require VT-x (see loukingjr post), and so could not run with Hyper-V, but from Legorol's experience this is possible - this is a contradiction that the Genymotion will need to solve.
- Genymotion can be using VirtualBox in any number of ways, which we don't know of.

You'll need to ask Genymotion people about Genymotion. The discussion about Hyper-V and VirtualBox has been covered now.

from their support page…

How do I run Genymotion on a Windows 8.X computer having Hyper-V installed?
Genymotion relies on the virtualization engine VirtualBox. It is impossible to use Oracle VM VirtualBox and Microsoft Hyper-V at the same time.
Therefore, to use Genymotion, you must disable Hyper-V when booting your computer.
To easily switch Hyper-V on or off on a Windows 8.X computer, please refer to this article.

Thank you for the clarification.
For my original issue, I am all set now after installing VB4.3.30.
I have been using Genymotion - VirutalBox - Hyper-V - Windows Phone emulators for about two years, and they work reliably.

I have the impression their wording is simply bad. They say "virtualization engine VirtualBox" but not "Virtualization feature" or "virtualization technology", which could lead to think they talk about VT-x, but are not.
And for the "It is impossible to use Oracle VM VirtualBox and Microsoft Hyper-V at the same time", it seems taken straight out of the manual/forum to avoid supporting situation that Oracle would not support.

and further more…

Why does my computer crash when I start Genymotion and also a virtualization engine such as VMWare or Parallels at the same time?
Genymotion relies on the virtualization engine VirtualBox.
Virtualization engines all use the same CPU resource. Running them at the same time is thus impossible and can lead to a crash of your operating system.
It is required that you do not start a virtualization engine at the same time as Genymotion.

I take it no one bothered to look at the link I posted with all people getting an error message from Genymotion saying VT-x was not available.

So it goes.

Sounds just like a "dumb" version of this warning. I did notice your link, but they didn't provide any log either.
And the very first result in your link, first (and unique) comment to the intial question actually states that disabling VT-x in the VirtualBox config made it work. Exactly the behaviour we're seeing here.

noteirak wrote:Sounds just like a "dumb" version of this warning.

So Max, basically you are saying the VirtualBox manual is wrong, dumb or at least misleading. Good to know.

How did you get there?
I said that the text from Genymotion, extracted into a quote 2 replies above mine is a dumb version of the warning in the VirtualBox manual.

Genymotion version is less precise which makes it missleading, including their poor choice of words.
VirtualBox verison is detailed and clear in what is and is not possible.

In case it is useful, the Acceleration tab under Settings > System is grayed out (4.3.30). If I remember correctly, this is not the case for VirtualBox 5.0. I believe I played the Acceleration tab of VirtualBox 5.0 a bit, but it did not make any difference.