This topic is new for Visual Studio 2005 SP1.
Deactivates virtual machine extensions (VMX) operation in the processor.
The __vmx_off function is equivalent to the VMXOFF machine instruction. This function supports the interaction of a host's virtual machine monitor with a guest operating system and its applications. For more information, search for the document, "Intel Virtualization Technical Specification for the IA-32 Intel Architecture," document number C97063-002, at the Intel Corporation site.