Download the Nasm Assembler from: https://www.nasm.us/pub/nasm/releasebuilds/2.12.02/win64/ and copy to C:/Nasm for Windows
Version 2.12.02 for Window X64:
https://www.nasm.us/pub/nasm/releasebuilds/2.12.02/win64/
Documentation 
http://www.nasm.us/doc/nasmdocc.html

