You may run across this error when compiling your Hybrid-App / Cordova application in Visual Studio. One of my students got it this week. It looks something like this:
This means that the install of the Cordova extensions did not work properly and you are missing some files. Mainly these two:
Simply uninstall (yeah, I know it takes a really long time to uninstall and reinstall). And the files should show up. If that doesn't work for you, install on another machine and copy over those directories. Then all will be fine!