Eclipse EE无法扩展名为'services'的文件夹

I am developing a mobile application using IBM Mobile First using AngularJS in Eclipse EE. I have a basic file structure containing folders 'controllers', 'directives', 'filters' and 'services'. The problem is with Eclipse: In the Project explorer I can't seem to expand the 'services' folder. I can see the content of the folder in Windows Explorer as well as Sublime Text File three. When I rename the folder to something else I can however expand it in Eclipse. I am developing a mobile application using IBM