MS Edge returns a HTTP404 Error for an ES6 Promise File

Current Situation

The MS Edge browser returns the following error message with every page call:

• HTTP404: NOT FOUND - The server has not found anything matching the requested URI (Uniform Resource Identifier).
  (XHR)GET - http://localhost:4446/joc/bower_components/es6-promise/dist/es6-promise.auto.map

Desired Behaviour

MS Edge should be able to load all the files called in page headers without error.