virtualbox.org

i get this error when i try to start a 64bit VM:

failed to start the virtual machine win2k8r2.
VT-x is not available. (VERR_VMX_NO_VMX).
Unknown error creating VM (VERR_VMX_NO_VMX).

and more details below (window does not allow to copy nothing from the error message, very annoying!)

I checked and my CPU supports VT-x.
CPU - Intel Xeon E5520

Also, My host is Windows 2008 R2 and it runs HyperV perfectly!

I created a new VM, selected to install fresh windows 2008 r2 and it won't start.

Am i missing something? Is this a bug?

Help please!

Nope no bug.
Look in your bios and turn on hardware-V. If it is not there then 64 bit guests will not work.

Thanks,

It is on, otherwise HyperV would not work. I had to turn it on for HyperV.

Anything else i can check?

Disable hyper-v.

you mean stop the service? there are no mahcines working in the same time.

Hyper-v = vbox, its one or the other, not both.

thanks for your real fast replies, but no luck.

I made sure VT is enabled in BIOS, stopped HyperV services and restarted my PC, made sure hyperV services are stopped again.

When i try to start the VM i get this error.

funny thing is, it does not allow me to uncheck the support for VT in the VM settings - the check boxes is checked and disabled.

any help is appreciated.
Thanks.

shaibs wrote:funny thing is, it does not allow me to uncheck the support for VT in the VM settings - the check boxes is checked and disabled.

Which indicates its not enabled or something else is (still) using it.

Ok,

It was the HyperV,
I had to completley uninstall it (not disable it) before virtual box could start.

After that my HyperV VHD's workd perfectly!

Thanks guys!