VirtualBox stopped working with the update to 10.8.2

Same here with a MB Retina...

Not happy that VirtualBox is broken since recent updates to MBA with Ivy-Bridge.

VB working fine on other 'nixes.

Looks like it might be time to wipe OS X and instal Linux or BSD instead.

:-(

I called Apple up, they seem to think they didn't disable hardware virtualization - VT-x just changed the way it can be accessed. If a way to access this isn't restored, the software virtualization route that will likely need to be taken is far from ideal. Especially since we had VT-x before this firmware upgrade.

This does not only affect VirtualBox, Parallells, or VMware though, it also affects things like CrossOver which is rather interesting.

It shoule be new EFI firmware problem.

I boot to external hard drive within 10.8.1 installed, VB still not work.

Running MBP Retina. Upgraded EFI and OS X 10.8.2. VirtualBox 4.2.0 wouldn't run because of the VT-x problem.

Downgraded to OS X 10.8, it's working again.

Hope this helps someone.

I also have this problem. macbook pro retina.

how to downgrade? to 10.8. ?

To downgrade to 10.8,

1. Grab a copy of the OS X 10.8 InstallESD.dmg.

2. Use Disk Utility to restore to a USB drive (minimum 8gb).

3. Boot from USB (Hold down Option key when booting).

4. Make sure you're disconnected from the Internet (prevents the installer from auto updating).

5. Select "Reinstall Mac OS X"

Same here. Just updated to 10.8.2 (12C54) and got the following error -

VT-x is being used by another hypervisor. (VERR_VMX_IN_VMX_ROOT_MODE).

VirtualBox can't operate in VMX root mode. Please close all other virtualization programs. (VERR_VMX_IN_VMX_ROOT_MODE).

Result Code: NS_ERROR_FAILURE (0x80004005)

Component: Console

Interface: IConsole {1968b7d3-e3bf-4ceb-99e0-cb7c913317bb}

There is now a hotfix available:

https://www.virtualbox.org/ticket/10965#comment:21

I've tested it with 10.8.2 and 4.1.23 and it's working now. Thanks to the VirtualBox guys for a quick turnaround.

Oracle released a patch which seems to do the trick.

You can find it at the end of this thread here: https://www.virtualbox.org/ticket/10965

Thanks to the folks at VirtualBox/Oracle for releasing a fix so quickly. My VMs are starting up just fine now.

Excellent work Oracle guys!!!

Cheers to the VirtualBox team for a quick resolution.

the fix is a superawesomething! 😀