I've installed Virtualbox on ubuntu 12.04 64 bit , but when I try installing Windows7 64bit I got this error message:
Failed to open a session for the virtual machine Microsoft.
VT-x features locked or unavailable in MSR. (VERR_VMX_MSR_LOCKED_OR_DISABLED).
Result Code: NS_ERROR_FAILURE (0x80004005) Component: Console Interface: IConsole {1968b7d3-e3bf-4ceb-99e0-cb7c913317bb}
thanks for your help