VirtualBox – Cannot start VM in Mac OS X 10.8.2

Using Mac Air 2012, upgraded to OS X 10.8.2 recently. Then, all VirtualBox’s VM images are unable to start, prompts 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).

P.S My VirtualBox version is 4.1.2

Try killed some suspected virtualization programs, restart VirtualBox and etc, but all useless. Actually, The error message is misleading, this is caused by the incompatible issue between VirtualBox and latest Mac OSX. Thanks VirtualBox is fast enough to release a hot fix v 4.2.1 for it.

To fix it, just download the latest or newer VirtualBox.

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