Intel HAXM is required to run this AVD ERROR AFTER INSTALLING HAXM

Haxm is already installed, VT-x in BIOS is enabled and we are working on Windows 7 Professional machine,but still when we run a virtual Device in AVD we get this error:

Intel HAXM is required to run this AVD.
/dev/kvm is not found.
Enable VT-x in your BIOS security settings, ensure that your Linux distro has working KVM module.

Screen shot of the error is attached.