Angular CLI - ng e2e throws error

I've just set up a new Angular 4 project using the Angular CLI. Just after creating it, I ran ng e2e and the sample end-to-end test executed perfectly. After this, I've added a subfolder inside the app folder called services, and generated a service inside that folder. Now, when I run ng e2e, it errors out with the following error:

[09:11:56] E/configParser - Error message: failed loading configuration file protractor.conf.js [09:11:56] E/configParser - Error: Cannot find module 'C:\Projects\new\test-project\src\app\services\protractor.conf.js

Any idea why this could be happening? I think I might need to prevent the e2e script from looking inside the services folder, but I'm not sure how to do that.