virtualbox.org

Everything was fine yesterday.
After I installed Android SDK (with Intel Hardware Accelerated Execution Manager) this morning on the host computer, I get this
error message "VT-x/AMD-V hardware acceleration not operational" when trying to start a virtual machine. Ignore the message, and the VM crashes.
I'm sure I didn't touch the VT-x setting in BIOS.
Tried uninstall Intel Hardware Accelerated Execution Manager, no effect.

Another Windows XP client VM started successfully, but the little "V" icon on the right bottom corner is grey (no hardware acceleration at all)

What did I done to make this happen???

I confirmed this IS a compatibility problem with Intel Hardware Accelerated Execution Manager (Intel haxm).
I uninstalled the whole Android SDK, and reinstalled it without the Intel haxm, restart my computer several times, now it's fine.

It seems haxm is locking VT-x resources so VirtualBox cannot access it. I don't know how to solve that.

But my VMware Player seems working properly. I can't be sure since I don't know how to check the VT-x status.

horeaper wrote:It seems haxm is locking VT-x resources so VirtualBox cannot access it. I don't know how to solve that.

Complain to Intel. Only they can fix that. If HAXM takes over VT-x, no one else can use it -- Intel designed it that way

But my VMware Player seems working properly. I can't be sure since I don't know how to check the VT-x status.

Working properly and using VT-x are two different things...

I updated to Intel HAXM R2 (download from Android SDK manager, then install from [ANDROID_SDK]/extras/intel/Hardware_Accelerated_Execution_Manager) and now I can run an x86 emulator and Virtualbox at the same time!

Does it still work for everyone?
So now HAXM is at version 1.1.1 released in October 2014, I'm running Windows 8.1 and still have this issue.
Virtual Box won't work until I reboot, install Hyper-V, reboot. And then to run HAXM (that is now mandatory for Android emulator), I need to uninstall Hyper-V again. What a piece of junk sigh.

Slightly off-topic, but now that Microsoft is supporting Android development with Visual Studio 2015, they recognize the problem of mutual exclusion between Intel HAXM and HyperV. However, they do realize the importance of HAXM to speed up Android emulators. So MS is "working on a solution" to this problem. I don't know the details about what the solution will be or when it might be available, but this has been communicated to mobile developers.