I removed the old version of grunt first, then I installed the new grunt version, and then I got this error:
D:\\www\\grunt-test\\grunt grunt-cli: The
Unable to find local Grunt
likely means that you have installed Grunt globally.
The Grunt CLI insists that you install grunt in your local node_modules directory, so Grunt is local to your project.
This will fail:
npm install -g grunt
Do this instead:
npm install grunt --save-dev