When installing or using Intel Hardware Accelerated Execution Manager (HAXM) or VMware Workstation on Windows, you may get an error message says that the system does not support VT-x. However you are sure that Intel Virtualization Technology is enabled in BIOS. It may be more confusing if you disable Virtualization Technology. The error message may say that the system has VT-x, but it is disabled. As it turns out that Hyper-V is the cause. When Hyper-V feature is turned on, it takes control of VT-x and make the system appear that it doesn not support VT-x. HAXM won’t let you install if it detects that the system does not support VT-x. When you disable Virtualization Technology in BIOS, HAXM installer detects the system supports VT-x and let you install it, but you can’t run it since VT-x is disabled in BIOS.
You just have to turn off Hyper-V feature if you want to use HAXM or WMware Workstation.