I have my NodeJS installed at C:\Apps\NodeJS and my project files are at D:\Projects\HTML[Project Name]\Code. I followed the install instructions found here, Installing Ember - Getting Started - Ember Guides with one exception. You have to install git first from this post where I documented the order: Ember CLI - the Ramcat way - #31 by Ramcat
Last trick I might mention (and is in the Guides) is that you have to launch the server from the directory below where you created the project. In other words, create the project “ember new app-name” via the command line (and from the folder above where you want the project created), then "cd app-name’, then run “ember server”.