Started building a VS2013 JS application for WP. But there is an error at compile time

Question

JavaScript

VS registered my HTC 8s wp8 as a developer phone.
True without buying a license.
Error 1 error during compile time in debug mode
Error : DEP6100 : The following unexpected error occurred during the bootstrap phase "Loading package '2b933ed0-1235-4338-95d8-43c033397dec'":
SmartDeviceException - Package not found at reference
App2
Error 2 Error : DEP6100 : The following unexpected error occurred during the 'Starting EDM3 Services' bootstrap step:
SmartDeviceException - Package not found at link

Answer 1

Do you have WP8.1 installed on your phone (or whichever is the latest)? And if so, is it also indicated in the project (meaning the target of the project)?