After running yo angular and then cd'ing into the application's root folder (at same level as the app folder, gruntfile, package.json etc) I try grunt serve and I get the above error. Grunt won't start a server for me.
I have searched all over but couldn't find say to run npm install and bower install within the application's root directory, which I have tried but still the same error.
I've updated and checked bower/grunt/npm and they're all good.
Any suggestions please?